From 0b8d5e719e79e21597ea0729d9349e07030a0e67 Mon Sep 17 00:00:00 2001
From: Srinivasa Consultants <78673153+dinakarjs@users.noreply.github.com>
Date: Thu, 22 Oct 2026 01:17:29 +0530
Subject: [PATCH 01/13] test: add pinned A2A TCK differential runner

Signed-off-by: Srinivasa Consultants <dinakarjs@gmail.com>
---
 experiments/a2a-tck/run.py | 117 +++++++++++++++++++++++++++++++++++++
 1 file changed, 117 insertions(+)
 create mode 100644 experiments/a2a-tck/run.py

diff --git a/experiments/a2a-tck/run.py b/experiments/a2a-tck/run.py
new file mode 100644
index 00000000..b38c6ef4
--- /dev/null
+++ b/experiments/a2a-tck/run.py
@@ -0,0 +1,117 @@
+"""Pinned, Linux-only differential TCK characterization of the existing SDK demo."""
+from __future__ import annotations
+
+import argparse
+import asyncio
+import hashlib
+import importlib.metadata
+import importlib.util
+import json
+import os
+import signal
+import subprocess
+import sys
+from pathlib import Path
+
+TCK_SHA = "5daf0144b4a4adbdefb62180739b13c5bd7d8196"
+ROOT = Path(__file__).resolve().parents[2]
+
+
+def git(path: Path, *args: str) -> str:
+    return subprocess.check_output(["git", "-C", str(path), *args], text=True).strip()
+
+
+async def run(args: argparse.Namespace) -> int:
+    if sys.platform != "linux":
+        raise SystemExit("This characterization runner requires Linux process groups")
+    tck = args.tck.resolve()
+    if git(tck, "rev-parse", "HEAD") != TCK_SHA:
+        raise SystemExit(f"TCK must be checked out at {TCK_SHA}")
+    if git(tck, "status", "--porcelain", "--untracked-files=no"):
+        raise SystemExit("TCK tracked files must be unchanged")
+    out = args.output.resolve()
+    out.mkdir(parents=True, exist_ok=False)
+    spec = importlib.util.spec_from_file_location("sdk_demo", ROOT / "examples/a2a-sdk/loopback.py")
+    assert spec and spec.loader
+    demo = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(demo)
+    original_card = demo.operator_card
+    scenario_spec = importlib.util.spec_from_file_location(
+        "tck_scenario", tck / "sut/a2a-python/sut_agent.py"
+    )
+    assert scenario_spec and scenario_spec.loader
+    scenario = importlib.util.module_from_spec(scenario_spec)
+    scenario_spec.loader.exec_module(scenario)
+
+    class ScenarioExecutor(demo.InventoryExecutor):
+        async def execute(self, context, event_queue):
+            message = context.message
+            metadata = demo.metadata_from_sdk_message(message) if message else {}
+            opted = message is not None and demo.EXTENSION_URI in message.extensions
+            if (demo.has_ca2a_metadata(metadata) or opted
+                    or demo.EXTENSION_URI in context.requested_extensions):
+                await super().execute(context, event_queue)
+            else:
+                await scenario.TckAgentExecutor().execute(context, event_queue)
+
+        async def cancel(self, context, event_queue):
+            await scenario.TckAgentExecutor().cancel(context, event_queue)
+
+    def card(url, node):
+        value = original_card(url, node)
+        value.capabilities.streaming = True
+        if args.mode == "baseline":
+            del value.capabilities.extensions[:]
+        return value
+
+    demo.operator_card = card
+    demo.InventoryExecutor = ScenarioExecutor
+    chain, _ = demo.demo_credentials()
+    node = demo.PeerNode(demo.LocalPolicy.of({demo.READ}), trusted_root_issuers={chain[0].issuer})
+    env = {key: value for key, value in os.environ.items()
+           if key.lower() not in {"http_proxy", "https_proxy", "all_proxy"}}
+    env["NO_PROXY"] = env["no_proxy"] = "127.0.0.1,localhost"
+    command = ["uv", "run", "--frozen", "python", "run_tck.py"]
+    async with demo.serve(node) as (url, executor):
+        command += ["--sut-host", url, "--transport", "jsonrpc", "--level", "must", "--",
+                    f"--compatibility-report={out / 'compatibility'}",
+                    f"--html={out / 'pytest.html'}", f"--junitxml={out / 'junit.xml'}"]
+        timed_out = False
+        with (out / "run.log").open("wb") as log:
+            process = await asyncio.create_subprocess_exec(
+                *command, cwd=tck, env=env, stdout=log, stderr=asyncio.subprocess.STDOUT,
+                start_new_session=True,
+            )
+            try:
+                code = await asyncio.wait_for(process.wait(), timeout=args.timeout)
+            except TimeoutError:
+                timed_out = True
+                os.killpg(process.pid, signal.SIGTERM)
+                try:
+                    await asyncio.wait_for(process.wait(), timeout=5)
+                except TimeoutError:
+                    os.killpg(process.pid, signal.SIGKILL)
+                    await process.wait()
+                code = 124
+        manifest = {
+            "mode": args.mode, "ca2a_commit": git(ROOT, "rev-parse", "HEAD"),
+            "ca2a_tracked_changes": git(ROOT, "status", "--porcelain", "--untracked-files=no"),
+            "runner_sha256": hashlib.sha256(Path(__file__).read_bytes()).hexdigest(),
+            "tck_commit": TCK_SHA,
+            "tck_lock_sha256": hashlib.sha256((tck / "uv.lock").read_bytes()).hexdigest(),
+            "python": sys.version, "sdk": importlib.metadata.version("a2a-sdk"),
+            "command": command, "exit_code": code, "timed_out": timed_out,
+            "protected_handler_invocations": executor.invocations,
+            "scope": "JSON-RPC MUST with pinned upstream scenario executor; cA2A ordinary-path differential",
+        }
+        (out / "manifest.json").write_text(json.dumps(manifest, indent=2) + "\n")
+    return code
+
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("--tck", type=Path, required=True)
+    parser.add_argument("--output", type=Path, required=True)
+    parser.add_argument("--mode", choices=["baseline", "extension"], required=True)
+    parser.add_argument("--timeout", type=float, default=180)
+    raise SystemExit(asyncio.run(run(parser.parse_args())))

From 871fdcd478688fa9cea64860398236e51ed72352 Mon Sep 17 00:00:00 2001
From: Srinivasa Consultants <78673153+dinakarjs@users.noreply.github.com>
Date: Thu, 22 Oct 2026 01:17:44 +0530
Subject: [PATCH 02/13] test: add experiments/a2a-tck/compare.py

Signed-off-by: Srinivasa Consultants <dinakarjs@gmail.com>
---
 experiments/a2a-tck/compare.py | 46 ++++++++++++++++++++++++++++++++++
 1 file changed, 46 insertions(+)
 create mode 100644 experiments/a2a-tck/compare.py

diff --git a/experiments/a2a-tck/compare.py b/experiments/a2a-tck/compare.py
new file mode 100644
index 00000000..5ba1661e
--- /dev/null
+++ b/experiments/a2a-tck/compare.py
@@ -0,0 +1,46 @@
+"""Fail on missing, failed, or changed per-test outcomes in paired TCK runs."""
+import argparse
+import json
+import sys
+import xml.etree.ElementTree as ET
+from collections import Counter
+from pathlib import Path
+
+
+def outcomes(directory):
+    manifest = json.loads((directory / 'manifest.json').read_text())
+    if manifest['exit_code'] != 0 or manifest['timed_out']:
+        raise ValueError('TCK run did not complete successfully')
+    rows = {}
+    for case in ET.parse(directory / 'junit.xml').iter('testcase'):
+        key = case.attrib['classname'] + '::' + case.attrib['name']
+        if key in rows:
+            raise ValueError('duplicate test identity: ' + key)
+        rows[key] = next((tag for tag in ('failure', 'error', 'skipped') if case.find(tag) is not None), 'passed')
+    if not rows or 'passed' not in rows.values():
+        raise ValueError('empty test coverage')
+    if any(status in {'failure', 'error'} for status in rows.values()):
+        raise ValueError('failed tests')
+    return manifest, rows
+
+
+def compare(baseline, extension):
+    left, a = outcomes(baseline)
+    right, b = outcomes(extension)
+    if left['mode'] != 'baseline' or right['mode'] != 'extension':
+        raise ValueError('expected baseline then extension')
+    for key in ('ca2a_commit', 'tck_commit', 'tck_lock_sha256', 'runner_sha256', 'sdk'):
+        if left[key] != right[key]:
+            raise ValueError('mismatched provenance: ' + key)
+    if a != b:
+        raise ValueError('per-test outcomes differ')
+    return {'identical_test_outcomes': True, 'counts': dict(Counter(a.values())),
+            'protected_handler_invocations': [left['protected_handler_invocations'], right['protected_handler_invocations']]}
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument('baseline', type=Path)
+    parser.add_argument('extension', type=Path)
+    args = parser.parse_args()
+    sys.stdout.write(json.dumps(compare(args.baseline, args.extension), indent=2) + "\n")

From 47e3105eff8d7b9e9b597bb650c7a5bf958cf4aa Mon Sep 17 00:00:00 2001
From: Srinivasa Consultants <78673153+dinakarjs@users.noreply.github.com>
Date: Thu, 22 Oct 2026 01:17:50 +0530
Subject: [PATCH 03/13] test: add experiments/a2a-tck/test_compare.py

Signed-off-by: Srinivasa Consultants <dinakarjs@gmail.com>
---
 experiments/a2a-tck/test_compare.py | 40 +++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)
 create mode 100644 experiments/a2a-tck/test_compare.py

diff --git a/experiments/a2a-tck/test_compare.py b/experiments/a2a-tck/test_compare.py
new file mode 100644
index 00000000..644ec761
--- /dev/null
+++ b/experiments/a2a-tck/test_compare.py
@@ -0,0 +1,40 @@
+"""Negative controls for the evidence comparator."""
+import json
+from pathlib import Path
+
+import pytest
+from compare import compare
+
+
+def write_run(root: Path, mode: str):
+    root.mkdir()
+    (root / 'manifest.json').write_text(json.dumps({
+        'mode': mode, 'exit_code': 0, 'timed_out': False,
+        'ca2a_commit': 'ca2a', 'tck_commit': 'tck', 'tck_lock_sha256': 'lock',
+        'runner_sha256': 'runner', 'sdk': '1.2.2', 'protected_handler_invocations': 0,
+    }))
+    (root / 'junit.xml').write_text('<testsuite><testcase classname="suite" name="one"/></testsuite>')
+
+
+@pytest.mark.parametrize('mutation', ['failure', 'missing', 'rename', 'skip', 'provenance', 'exit'])
+def test_rejects_false_equivalence(tmp_path, mutation):
+    left, right = tmp_path / 'baseline', tmp_path / 'extension'
+    write_run(left, 'baseline')
+    write_run(right, 'extension')
+    assert compare(left, right)['identical_test_outcomes']
+    path = right / 'junit.xml'
+    if mutation == 'failure':
+        path.write_text('<testsuite><testcase classname="suite" name="one"><failure/></testcase></testsuite>')
+    elif mutation == 'missing':
+        path.write_text('<testsuite/>')
+    elif mutation == 'rename':
+        path.write_text(path.read_text().replace('one', 'two'))
+    elif mutation == 'skip':
+        path.write_text('<testsuite><testcase classname="suite" name="one"><skipped/></testcase></testsuite>')
+    else:
+        path = right / 'manifest.json'
+        data = json.loads(path.read_text())
+        data['sdk' if mutation == 'provenance' else 'exit_code'] = 'changed'
+        path.write_text(json.dumps(data))
+    with pytest.raises(ValueError):
+        compare(left, right)

From 9276476f01a78e91096665d3b5846afd4cf5d3b9 Mon Sep 17 00:00:00 2001
From: Srinivasa Consultants <78673153+dinakarjs@users.noreply.github.com>
Date: Thu, 22 Oct 2026 01:17:56 +0530
Subject: [PATCH 04/13] test: add experiments/a2a-tck/environment.txt

Signed-off-by: Srinivasa Consultants <dinakarjs@gmail.com>
---
 experiments/a2a-tck/environment.txt | 97 +++++++++++++++++++++++++++++
 1 file changed, 97 insertions(+)
 create mode 100644 experiments/a2a-tck/environment.txt

diff --git a/experiments/a2a-tck/environment.txt b/experiments/a2a-tck/environment.txt
new file mode 100644
index 00000000..45b4f4d0
--- /dev/null
+++ b/experiments/a2a-tck/environment.txt
@@ -0,0 +1,97 @@
+a2a-sdk==1.2.2
+agent-manifest==0.15.0
+agentrust-trace==0.11.0
+agentrust-trace-tests==0.6.2
+aiohappyeyeballs==2.7.1
+aiohttp==3.14.5
+aiologic==0.17.1
+aiosignal==1.4.0
+annotated-types==0.8.0
+anyio==4.15.1
+ast-serialize==0.13.0
+attrs==26.1.0
+bandit==1.9.4
+boolean-py==5.0
+cachecontrol==0.14.4
+cbor2==6.1.4
+cedarpy==4.12.1
+certifi==2026.7.22
+cffi==2.1.1
+charset-normalizer==3.5.1
+click==8.5.0
+coverage==7.16.0
+cryptography==50.0.1
+culsans==0.11.0
+cyclonedx-python-lib==11.12.0
+defusedxml==0.7.1
+filelock==3.32.5
+frozenlist==1.8.0
+google-api-core==2.36.0
+google-auth==2.57.1
+googleapis-common-protos==1.75.3
+grpcio==1.84.0
+grpcio-reflection==1.84.0
+grpcio-tools==1.84.0
+h11==0.16.0
+httpcore==1.0.9
+httpx==0.28.1
+idna==3.19
+iniconfig==2.3.0
+json-rpc==1.15.0
+jsonschema==4.26.0
+jsonschema-specifications==2025.9.1
+librt==0.16.0
+license-expression==30.4.4
+markdown-it-py==4.2.0
+mdurl==0.1.2
+msgpack==1.2.2
+multidict==6.9.1
+mypy==2.4.0
+mypy-extensions==1.1.0
+opentelemetry-api==1.44.0
+packageurl-python==0.17.6
+packaging==26.3
+pathspec==1.1.1
+pip==26.2.1
+pip-api==0.0.34
+pip-audit==2.10.1
+pip-requirements-parser==32.0.1
+platformdirs==4.13.1
+pluggy==1.6.0
+propcache==0.5.2
+proto-plus==1.28.4
+protobuf==7.36.2
+py-serializable==2.1.0
+pyasn1==0.6.4
+pyasn1-modules==0.4.2
+pycparser==3.0
+pydantic==2.13.5
+pydantic-core==2.46.5
+pygments==2.21.0
+pyparsing==3.3.2
+pytest==9.1.1
+pytest-asyncio==1.4.0
+pytest-cov==7.1.0
+pyyaml==6.0.3
+referencing==0.37.0
+requests==2.34.2
+rfc3986-validator==0.1.1
+rfc8785==0.1.4
+rich==15.0.0
+rpds-py==2026.6.3
+ruff==0.17.1
+setuptools==84.0.0
+sniffio==1.3.1
+sortedcontainers==2.4.0
+sse-starlette==3.4.11
+starlette==1.6.0
+stevedore==5.9.1
+tomli==2.4.1
+tomli-w==1.2.0
+types-pyyaml==6.0.12.20260906
+typing-extensions==4.16.0
+typing-inspection==0.4.4
+urllib3==2.8.0
+uvicorn==0.54.0
+wrapt==2.4.0
+yarl==1.25.1

From 4d526d079b135a94ece9bff39e852523ea4f99ea Mon Sep 17 00:00:00 2001
From: Srinivasa Consultants <78673153+dinakarjs@users.noreply.github.com>
Date: Thu, 22 Oct 2026 01:18:17 +0530
Subject: [PATCH 05/13] test: add experiments/a2a-tck/README.md

Signed-off-by: Srinivasa Consultants <dinakarjs@gmail.com>
---
 experiments/a2a-tck/README.md | 51 +++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)
 create mode 100644 experiments/a2a-tck/README.md

diff --git a/experiments/a2a-tck/README.md b/experiments/a2a-tck/README.md
new file mode 100644
index 00000000..dae5ee46
--- /dev/null
+++ b/experiments/a2a-tck/README.md
@@ -0,0 +1,51 @@
+# Pinned A2A ordinary-path compatibility experiment
+
+The runner serves the existing cA2A SDK loopback adapter with the official TCK's
+scenario executor for ordinary messages. Protected messages retain the existing
+cA2A executor. Both modes are cA2A-aware: `baseline` only removes the extension
+advertisement. This isolates advertisement compatibility; it is not a comparison
+against a separate, unmodified SDK server or a protected-path TCK certification.
+
+Test dependencies and upstream scenario code are isolated from runtime packages.
+Linux and Python 3.12 are required. From the repository root:
+
+```sh
+git clone https://github.com/a2aproject/a2a-tck.git ../a2a-tck
+git -C ../a2a-tck checkout 5daf0144b4a4adbdefb62180739b13c5bd7d8196
+uv venv --python 3.12 ../ca2a-tck-sut
+uv pip install --python ../ca2a-tck-sut/bin/python -r experiments/a2a-tck/environment.txt
+export UV_PROJECT_ENVIRONMENT="$(cd .. && pwd)/tck-clean-env"
+(cd ../a2a-tck && uv sync --frozen)
+PYTHONPATH=src ../ca2a-tck-sut/bin/python experiments/a2a-tck/run.py --tck ../a2a-tck --output ../tck-baseline-results --mode baseline
+PYTHONPATH=src ../ca2a-tck-sut/bin/python experiments/a2a-tck/run.py --tck ../a2a-tck --output ../tck-extension-results --mode extension
+python experiments/a2a-tck/compare.py ../tck-baseline-results ../tck-extension-results
+PYTHONPATH=src ../ca2a-tck-sut/bin/python -m pytest tests/unit/test_a2a_sdk_bridge.py tests/unit/test_a2a_sdk_loopback.py
+```
+
+Output directories must be new. Each run retains logs, JUnit, HTML, compatibility
+report, dependency/source identifiers, timeout status and protected-handler count.
+The comparison rejects unsuccessful runs, changed test identities/outcomes and
+mismatched provenance. Skips remain skips. Inherited proxies are cleared only for
+the local TCK child. Timeout cleanup terminates its process group.
+
+## Observed result
+
+On cA2A `806d1147c0bc834ee8aabb698b341c926cd8531e`, A2A SDK 1.2.2,
+Python 3.12.14 and the pinned TCK above:
+
+| Check | Result |
+| --- | --- |
+| Baseline JSON-RPC MUST | 79 passed, 156 skipped, 30 deselected |
+| Extension-advertised JSON-RPC MUST | 79 passed, 156 skipped, 30 deselected |
+| Per-test identity/outcome comparison | identical |
+| Protected handler calls in either TCK run | 0 |
+| Separate cA2A bridge + signed loopback suite | 55 passed |
+| Dependency consistency | `uv pip check` passed |
+
+Initial runs using the immediate-response inventory demo instead of the upstream
+scenario executor had five task/artifact/text failures in both modes. They were
+fixture coverage gaps; this change makes no production compatibility fix.
+
+This does not cover HTTP+JSON, gRPC, SHOULD/MAY, real hardware attestation,
+independent Go/JavaScript SDKs or cross-language cryptographic interoperability.
+The existing signed loopback tests are separate evidence, not TCK coverage.

From 34b150e435861365f476a5d1bd51966d2ab80705 Mon Sep 17 00:00:00 2001
From: Srinivasa Consultants <78673153+dinakarjs@users.noreply.github.com>
Date: Thu, 22 Oct 2026 01:19:14 +0530
Subject: [PATCH 06/13] ci: run pinned A2A differential and retain evidence

Signed-off-by: Srinivasa Consultants <dinakarjs@gmail.com>
---
 .github/workflows/a2a-tck.yml | 44 +++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)
 create mode 100644 .github/workflows/a2a-tck.yml

diff --git a/.github/workflows/a2a-tck.yml b/.github/workflows/a2a-tck.yml
new file mode 100644
index 00000000..6e0cdfca
--- /dev/null
+++ b/.github/workflows/a2a-tck.yml
@@ -0,0 +1,44 @@
+name: Pinned A2A ordinary-path TCK
+on:
+  workflow_dispatch:
+  pull_request:
+    paths:
+      - 'experiments/a2a-tck/**'
+      - 'examples/a2a-sdk/**'
+      - '.github/workflows/a2a-tck.yml'
+permissions:
+  contents: read
+jobs:
+  differential:
+    runs-on: ubuntu-latest
+    timeout-minutes: 15
+    steps:
+      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
+      - uses: actions/setup-python@5fda3b95a4ea91299a34e894583c3862153e4b97 # v7.0.0
+        with:
+          python-version: '3.12'
+      - name: Prepare isolated pinned environments
+        run: |
+          python -m pip install uv==0.12.23
+          uv venv --python 3.12 ../ca2a-tck-sut
+          uv pip install --python ../ca2a-tck-sut/bin/python -r experiments/a2a-tck/environment.txt
+          git clone https://github.com/a2aproject/a2a-tck.git ../a2a-tck
+          git -C ../a2a-tck checkout 5daf0144b4a4adbdefb62180739b13c5bd7d8196
+          cd ../a2a-tck
+          UV_PROJECT_ENVIRONMENT="$RUNNER_TEMP/tck-env" uv sync --frozen
+      - name: Run paired TCK and protected cA2A tests
+        env:
+          PYTHONPATH: src
+          UV_PROJECT_ENVIRONMENT: ${{ runner.temp }}/tck-env
+        run: |
+          ../ca2a-tck-sut/bin/python experiments/a2a-tck/run.py --tck ../a2a-tck --output ../tck-baseline-results --mode baseline
+          ../ca2a-tck-sut/bin/python experiments/a2a-tck/run.py --tck ../a2a-tck --output ../tck-extension-results --mode extension
+          python experiments/a2a-tck/compare.py ../tck-baseline-results ../tck-extension-results
+          ../ca2a-tck-sut/bin/python -m pytest experiments/a2a-tck/test_compare.py tests/unit/test_a2a_sdk_bridge.py tests/unit/test_a2a_sdk_loopback.py
+      - uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.0
+        if: always()
+        with:
+          name: a2a-tck-evidence
+          path: |
+            ../tck-baseline-results
+            ../tck-extension-results

From 46f10359e13fea22801383d298d491b4fdda00c0 Mon Sep 17 00:00:00 2001
From: Srinivasa Consultants <78673153+dinakarjs@users.noreply.github.com>
Date: Thu, 22 Oct 2026 01:22:51 +0530
Subject: [PATCH 07/13] fix: keep TCK artifact paths within workspace

Signed-off-by: Srinivasa Consultants <dinakarjs@gmail.com>
---
 .github/workflows/a2a-tck.yml | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/a2a-tck.yml b/.github/workflows/a2a-tck.yml
index 6e0cdfca..6d659645 100644
--- a/.github/workflows/a2a-tck.yml
+++ b/.github/workflows/a2a-tck.yml
@@ -31,14 +31,14 @@ jobs:
           PYTHONPATH: src
           UV_PROJECT_ENVIRONMENT: ${{ runner.temp }}/tck-env
         run: |
-          ../ca2a-tck-sut/bin/python experiments/a2a-tck/run.py --tck ../a2a-tck --output ../tck-baseline-results --mode baseline
-          ../ca2a-tck-sut/bin/python experiments/a2a-tck/run.py --tck ../a2a-tck --output ../tck-extension-results --mode extension
-          python experiments/a2a-tck/compare.py ../tck-baseline-results ../tck-extension-results
+          ../ca2a-tck-sut/bin/python experiments/a2a-tck/run.py --tck ../a2a-tck --output tck-baseline-results --mode baseline
+          ../ca2a-tck-sut/bin/python experiments/a2a-tck/run.py --tck ../a2a-tck --output tck-extension-results --mode extension
+          python experiments/a2a-tck/compare.py tck-baseline-results tck-extension-results
           ../ca2a-tck-sut/bin/python -m pytest experiments/a2a-tck/test_compare.py tests/unit/test_a2a_sdk_bridge.py tests/unit/test_a2a_sdk_loopback.py
       - uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.0
         if: always()
         with:
           name: a2a-tck-evidence
           path: |
-            ../tck-baseline-results
-            ../tck-extension-results
+            tck-baseline-results
+            tck-extension-results

From d312e90307c0fe679101afb28a43a6d19554d3f0 Mon Sep 17 00:00:00 2001
From: Srinivasa Consultants <78673153+dinakarjs@users.noreply.github.com>
Date: Thu, 22 Oct 2026 01:25:07 +0530
Subject: [PATCH 08/13] fix: pin patched certifi in isolated TCK environment

Signed-off-by: Srinivasa Consultants <dinakarjs@gmail.com>
---
 experiments/a2a-tck/environment.txt | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/experiments/a2a-tck/environment.txt b/experiments/a2a-tck/environment.txt
index 45b4f4d0..781fc446 100644
--- a/experiments/a2a-tck/environment.txt
+++ b/experiments/a2a-tck/environment.txt
@@ -15,7 +15,7 @@ boolean-py==5.0
 cachecontrol==0.14.4
 cbor2==6.1.4
 cedarpy==4.12.1
-certifi==2026.7.22
+certifi==2026.10.19
 cffi==2.1.1
 charset-normalizer==3.5.1
 click==8.5.0

From 9d1a54dea2a375257ffdce08894b3f01e72e8031 Mon Sep 17 00:00:00 2001
From: Srinivasa Consultants <78673153+dinakarjs@users.noreply.github.com>
Date: Mon, 2 Nov 2026 15:49:47 +0530
Subject: [PATCH 09/13] fix(tck): enforce zero protected-handler counts in
 comparison

Reject nonzero or malformed protected-handler counts and dirty tracked source. Cover unequal and equal nonzero counts with valid twins. Clarify the counter and streaming fixture, reject untracked TCK changes, clear inherited pytest options, and schedule on source/dependency changes.

Prepared with OpenAI Codex.

Signed-off-by: Srinivasa Dinakar Jainti <dinakarjs@gmail.com>
---
 .github/workflows/a2a-tck.yml       |  3 +++
 experiments/a2a-tck/README.md       | 17 ++++++++++++----
 experiments/a2a-tck/compare.py      |  6 ++++++
 experiments/a2a-tck/run.py          |  7 ++++---
 experiments/a2a-tck/test_compare.py | 31 ++++++++++++++++++++++++++++-
 5 files changed, 56 insertions(+), 8 deletions(-)

diff --git a/.github/workflows/a2a-tck.yml b/.github/workflows/a2a-tck.yml
index 6d659645..00b1f9ca 100644
--- a/.github/workflows/a2a-tck.yml
+++ b/.github/workflows/a2a-tck.yml
@@ -5,6 +5,9 @@ on:
     paths:
       - 'experiments/a2a-tck/**'
       - 'examples/a2a-sdk/**'
+      - 'src/**'
+      - 'requirements/**'
+      - 'pyproject.toml'
       - '.github/workflows/a2a-tck.yml'
 permissions:
   contents: read
diff --git a/experiments/a2a-tck/README.md b/experiments/a2a-tck/README.md
index dae5ee46..502ca251 100644
--- a/experiments/a2a-tck/README.md
+++ b/experiments/a2a-tck/README.md
@@ -2,8 +2,8 @@
 
 The runner serves the existing cA2A SDK loopback adapter with the official TCK's
 scenario executor for ordinary messages. Protected messages retain the existing
-cA2A executor. Both modes are cA2A-aware: `baseline` only removes the extension
-advertisement. This isolates advertisement compatibility; it is not a comparison
+cA2A executor. Both modes are cA2A-aware, and both enable streaming for the pinned scenario executor.
+The differential between the two modes is only the extension advertisement. This isolates advertisement compatibility; it is not a comparison
 against a separate, unmodified SDK server or a protected-path TCK certification.
 
 Test dependencies and upstream scenario code are isolated from runtime packages.
@@ -25,8 +25,12 @@ PYTHONPATH=src ../ca2a-tck-sut/bin/python -m pytest tests/unit/test_a2a_sdk_brid
 Output directories must be new. Each run retains logs, JUnit, HTML, compatibility
 report, dependency/source identifiers, timeout status and protected-handler count.
 The comparison rejects unsuccessful runs, changed test identities/outcomes and
-mismatched provenance. Skips remain skips. Inherited proxies are cleared only for
-the local TCK child. Timeout cleanup terminates its process group.
+mismatched provenance, modified tracked cA2A source, and any protected-handler
+count other than integer zero on either side. The counter measures successful
+protected `_lookup()` invocations after authentication and payload checks; it
+does not count early protected-path refusals or prove that path was never entered.
+Skips remain skips. The TCK checkout must have no tracked or untracked changes.
+Inherited proxies and `PYTEST_*` settings are cleared for the local TCK child. Timeout cleanup terminates its process group.
 
 ## Observed result
 
@@ -49,3 +53,8 @@ fixture coverage gaps; this change makes no production compatibility fix.
 This does not cover HTTP+JSON, gRPC, SHOULD/MAY, real hardware attestation,
 independent Go/JavaScript SDKs or cross-language cryptographic interoperability.
 The existing signed loopback tests are separate evidence, not TCK coverage.
+
+The environment and action pins remain the historical experiment's fixed inputs;
+they are not claims to track the latest dependency or action versions. Updating
+those pins and remeasuring is a separate comparison. Current comparator controls
+do not re-date the historical observed TCK results below.
diff --git a/experiments/a2a-tck/compare.py b/experiments/a2a-tck/compare.py
index 5ba1661e..f3925f1d 100644
--- a/experiments/a2a-tck/compare.py
+++ b/experiments/a2a-tck/compare.py
@@ -32,6 +32,12 @@ def compare(baseline, extension):
     for key in ('ca2a_commit', 'tck_commit', 'tck_lock_sha256', 'runner_sha256', 'sdk'):
         if left[key] != right[key]:
             raise ValueError('mismatched provenance: ' + key)
+    for manifest in (left, right):
+        count = manifest.get('protected_handler_invocations')
+        if type(count) is not int or count != 0:
+            raise ValueError('protected-handler count must be integer zero')
+        if manifest.get('ca2a_tracked_changes') != '':
+            raise ValueError('cA2A tracked files must be unchanged')
     if a != b:
         raise ValueError('per-test outcomes differ')
     return {'identical_test_outcomes': True, 'counts': dict(Counter(a.values())),
diff --git a/experiments/a2a-tck/run.py b/experiments/a2a-tck/run.py
index b38c6ef4..729fdb98 100644
--- a/experiments/a2a-tck/run.py
+++ b/experiments/a2a-tck/run.py
@@ -27,8 +27,8 @@ async def run(args: argparse.Namespace) -> int:
     tck = args.tck.resolve()
     if git(tck, "rev-parse", "HEAD") != TCK_SHA:
         raise SystemExit(f"TCK must be checked out at {TCK_SHA}")
-    if git(tck, "status", "--porcelain", "--untracked-files=no"):
-        raise SystemExit("TCK tracked files must be unchanged")
+    if git(tck, "status", "--porcelain", "--untracked-files=all"):
+        raise SystemExit("TCK checkout must have no tracked or untracked changes")
     out = args.output.resolve()
     out.mkdir(parents=True, exist_ok=False)
     spec = importlib.util.spec_from_file_location("sdk_demo", ROOT / "examples/a2a-sdk/loopback.py")
@@ -69,7 +69,8 @@ def card(url, node):
     chain, _ = demo.demo_credentials()
     node = demo.PeerNode(demo.LocalPolicy.of({demo.READ}), trusted_root_issuers={chain[0].issuer})
     env = {key: value for key, value in os.environ.items()
-           if key.lower() not in {"http_proxy", "https_proxy", "all_proxy"}}
+           if key.lower() not in {"http_proxy", "https_proxy", "all_proxy"}
+           and not key.startswith("PYTEST_")}
     env["NO_PROXY"] = env["no_proxy"] = "127.0.0.1,localhost"
     command = ["uv", "run", "--frozen", "python", "run_tck.py"]
     async with demo.serve(node) as (url, executor):
diff --git a/experiments/a2a-tck/test_compare.py b/experiments/a2a-tck/test_compare.py
index 644ec761..aaf5b6d3 100644
--- a/experiments/a2a-tck/test_compare.py
+++ b/experiments/a2a-tck/test_compare.py
@@ -9,7 +9,7 @@
 def write_run(root: Path, mode: str):
     root.mkdir()
     (root / 'manifest.json').write_text(json.dumps({
-        'mode': mode, 'exit_code': 0, 'timed_out': False,
+        'mode': mode, 'exit_code': 0, 'timed_out': False, 'ca2a_tracked_changes': '',
         'ca2a_commit': 'ca2a', 'tck_commit': 'tck', 'tck_lock_sha256': 'lock',
         'runner_sha256': 'runner', 'sdk': '1.2.2', 'protected_handler_invocations': 0,
     }))
@@ -38,3 +38,32 @@ def test_rejects_false_equivalence(tmp_path, mutation):
         path.write_text(json.dumps(data))
     with pytest.raises(ValueError):
         compare(left, right)
+
+
+@pytest.mark.parametrize('counts', [(0, 7), (7, 0), (7, 7), (False, 0), (0, 0.0), (0, None), (0, -1)])
+def test_protected_handler_zero_is_enforced(tmp_path, counts):
+    left, right = tmp_path / 'baseline', tmp_path / 'extension'
+    write_run(left, 'baseline')
+    write_run(right, 'extension')
+    assert compare(left, right)['protected_handler_invocations'] == [0, 0]
+    for root, count in zip((left, right), counts, strict=True):
+        path = root / 'manifest.json'
+        data = json.loads(path.read_text())
+        data['protected_handler_invocations'] = count
+        path.write_text(json.dumps(data))
+    with pytest.raises(ValueError, match='protected-handler'):
+        compare(left, right)
+
+
+@pytest.mark.parametrize('mode', ['baseline', 'extension'])
+def test_dirty_source_cannot_compare_equal(tmp_path, mode):
+    left, right = tmp_path / 'baseline', tmp_path / 'extension'
+    write_run(left, 'baseline')
+    write_run(right, 'extension')
+    root = left if mode == 'baseline' else right
+    path = root / 'manifest.json'
+    data = json.loads(path.read_text())
+    data['ca2a_tracked_changes'] = ' M src/ca2a_runtime/peer.py'
+    path.write_text(json.dumps(data))
+    with pytest.raises(ValueError, match='tracked files'):
+        compare(left, right)

From 306f91f46fe64953977b29d82024233f8cb241b1 Mon Sep 17 00:00:00 2001
From: Srinivasa Consultants <78673153+dinakarjs@users.noreply.github.com>
Date: Mon, 2 Nov 2026 15:56:46 +0530
Subject: [PATCH 10/13] fix(deps): carry reviewed pyasn1 floor from #303

Carry the exact reviewed #303 dependency input, lock and SDK/dev-extra floors into this branch to clear the current hosted security audit failure. Preserve this PR's own runtime/tests and changelog entry. No security gate is bypassed.

Prepared with OpenAI Codex.

Signed-off-by: Srinivasa Dinakar Jainti <dinakarjs@gmail.com>
---
 CHANGELOG.md         |  4 ++++
 pyproject.toml       |  2 ++
 requirements/dev.in  |  3 +++
 requirements/dev.txt | 10 ++++++----
 4 files changed, 15 insertions(+), 4 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index caaf5e60..e706403d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- Raise the A2A SDK and development extras' `pyasn1` security floor to 0.6.5,
+  alongside the development/CI hash lock, clearing four dependency-audit
+  findings for 0.6.4.
+
 - Sealing to a low-order X25519 peer key raises `SealedChannelError`, consistent
   with other invalid channel keys, instead of leaking a backend `ValueError`.
   These keys were already refused; no ciphertext format or acceptance rule changes.
diff --git a/pyproject.toml b/pyproject.toml
index 4cf4691a..f6515ffe 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -49,6 +49,7 @@ tpm = [
 a2a-sdk = [
     "a2a-sdk>=1.1,<2",
     "aiohttp>=3.14.3",
+    "pyasn1>=0.6.5",
 ]
 dev = [
     "pytest>=8.0",
@@ -66,6 +67,7 @@ dev = [
     "a2a-sdk[http-server]==1.2.2",
     "uvicorn==0.54.0",
     "aiohttp>=3.14.3",
+    "pyasn1>=0.6.5",
 ]
 
 [project.scripts]
diff --git a/requirements/dev.in b/requirements/dev.in
index ad636eff..36a848d0 100644
--- a/requirements/dev.in
+++ b/requirements/dev.in
@@ -25,3 +25,6 @@ a2a-sdk[http-server]==1.2.2
 uvicorn==0.54.0
 aiohttp>=3.14.3
 setuptools>=83.0.0
+
+# Security floor for google-auth's transitive ASN.1 dependency (four audit findings).
+pyasn1>=0.6.5
diff --git a/requirements/dev.txt b/requirements/dev.txt
index a57d254f..981e67dc 100644
--- a/requirements/dev.txt
+++ b/requirements/dev.txt
@@ -1710,10 +1710,12 @@ py-serializable==2.1.0 \
     --hash=sha256:9d5db56154a867a9b897c0163b33a793c804c80cee984116d02d49e4578fc103 \
     --hash=sha256:b56d5d686b5a03ba4f4db5e769dc32336e142fc3bd4d68a8c25579ebb0a67304
     # via cyclonedx-python-lib
-pyasn1==0.6.4 \
-    --hash=sha256:9c447d8431c947fe4c8febc4ed9e760bc29011a5b01e5c74b67025bd9fb8ce81 \
-    --hash=sha256:deda9277cfd454080ec40b207fb6df82206a3a2688735233cdcd8d3d565f088b
-    # via pyasn1-modules
+pyasn1==0.6.5 \
+    --hash=sha256:4017b0fce125096b8573b39c989fdb1a4b19cf761e683398184550fea0e66587 \
+    --hash=sha256:6b11616a6bcf3a40e635f082bb232fa57b5e0dd7f517bd7ddd69ec3794508a47
+    # via
+    #   -r requirements/dev.in
+    #   pyasn1-modules
 pyasn1-modules==0.4.2 \
     --hash=sha256:29253a9207ce32b64c3ac6600edc75368f98473906e8fd1043bd6b5b1de2c14a \
     --hash=sha256:677091de870a80aae844b1ca6134f54652fa2c8c5a52aa396440ac3106e941e6

From 3fbd9a3f2a7b3a65a1f2c59651df202614f8d0f1 Mon Sep 17 00:00:00 2001
From: Srinivasa Consultants <78673153+dinakarjs@users.noreply.github.com>
Date: Tue, 3 Nov 2026 09:20:03 +0530
Subject: [PATCH 11/13] fix(deps): update experimental TCK pyasn1 pin

Update the TCK SUT environment to pyasn1 0.6.5 and explain the security exception to historical pins. Preserve historical results and existing verification boundaries.

Prepared with OpenAI Codex.

Signed-off-by: Srinivasa Dinakar Jainti <dinakarjs@gmail.com>
---
 experiments/a2a-tck/README.md       | 14 ++++++++++----
 experiments/a2a-tck/environment.txt |  2 +-
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/experiments/a2a-tck/README.md b/experiments/a2a-tck/README.md
index 502ca251..2a84450e 100644
--- a/experiments/a2a-tck/README.md
+++ b/experiments/a2a-tck/README.md
@@ -54,7 +54,13 @@ This does not cover HTTP+JSON, gRPC, SHOULD/MAY, real hardware attestation,
 independent Go/JavaScript SDKs or cross-language cryptographic interoperability.
 The existing signed loopback tests are separate evidence, not TCK coverage.
 
-The environment and action pins remain the historical experiment's fixed inputs;
-they are not claims to track the latest dependency or action versions. Updating
-those pins and remeasuring is a separate comparison. Current comparator controls
-do not re-date the historical observed TCK results below.
+The environment and action pins remain the historical experiment's fixed inputs,
+except that `environment.txt` now pins `pyasn1==0.6.5` to carry the security fix
+into the SUT interpreter installed by the TCK workflow. The #303 dependency-floor
+update did not cover this experimental installation path. Other pins, including
+`cedarpy` and action SHAs, are unchanged; updating them and remeasuring remains a
+separate comparison. These pins are not claims to track the latest versions.
+This security update and the current comparator controls do not re-date the
+historical observed TCK results above, measured at cA2A
+`806d1147c0bc834ee8aabb698b341c926cd8531e`; they are not results for the updated
+environment.
diff --git a/experiments/a2a-tck/environment.txt b/experiments/a2a-tck/environment.txt
index 781fc446..1acd3f3d 100644
--- a/experiments/a2a-tck/environment.txt
+++ b/experiments/a2a-tck/environment.txt
@@ -62,7 +62,7 @@ propcache==0.5.2
 proto-plus==1.28.4
 protobuf==7.36.2
 py-serializable==2.1.0
-pyasn1==0.6.4
+pyasn1==0.6.5
 pyasn1-modules==0.4.2
 pycparser==3.0
 pydantic==2.13.5

From 98f4fd69d789509ea81be8aa2a43870d586d91cb Mon Sep 17 00:00:00 2001
From: Srinivasa Consultants <78673153+dinakarjs@users.noreply.github.com>
Date: Tue, 3 Nov 2026 19:36:01 +0530
Subject: [PATCH 12/13] fix(tck): remediate and audit experimental dependencies

Triage 15 known advisory findings and update four SUT pins. Retain historical measurements and audit the installed SUT before TCK execution.

Prepared with OpenAI Codex.

Signed-off-by: Srinivasa Dinakar Jainti <dinakarjs@gmail.com>
---
 .github/workflows/a2a-tck.yml            |  2 +
 experiments/a2a-tck/README.md            | 22 +++++----
 experiments/a2a-tck/dependency-triage.md | 58 ++++++++++++++++++++++++
 experiments/a2a-tck/environment.txt      |  8 ++--
 4 files changed, 76 insertions(+), 14 deletions(-)
 create mode 100644 experiments/a2a-tck/dependency-triage.md

diff --git a/.github/workflows/a2a-tck.yml b/.github/workflows/a2a-tck.yml
index 00b1f9ca..02a0cadd 100644
--- a/.github/workflows/a2a-tck.yml
+++ b/.github/workflows/a2a-tck.yml
@@ -25,6 +25,8 @@ jobs:
           python -m pip install uv==0.12.23
           uv venv --python 3.12 ../ca2a-tck-sut
           uv pip install --python ../ca2a-tck-sut/bin/python -r experiments/a2a-tck/environment.txt
+          ../ca2a-tck-sut/bin/python -m pip check
+          ../ca2a-tck-sut/bin/python -m pip_audit
           git clone https://github.com/a2aproject/a2a-tck.git ../a2a-tck
           git -C ../a2a-tck checkout 5daf0144b4a4adbdefb62180739b13c5bd7d8196
           cd ../a2a-tck
diff --git a/experiments/a2a-tck/README.md b/experiments/a2a-tck/README.md
index 2a84450e..64faa046 100644
--- a/experiments/a2a-tck/README.md
+++ b/experiments/a2a-tck/README.md
@@ -54,13 +54,15 @@ This does not cover HTTP+JSON, gRPC, SHOULD/MAY, real hardware attestation,
 independent Go/JavaScript SDKs or cross-language cryptographic interoperability.
 The existing signed loopback tests are separate evidence, not TCK coverage.
 
-The environment and action pins remain the historical experiment's fixed inputs,
-except that `environment.txt` now pins `pyasn1==0.6.5` to carry the security fix
-into the SUT interpreter installed by the TCK workflow. The #303 dependency-floor
-update did not cover this experimental installation path. Other pins, including
-`cedarpy` and action SHAs, are unchanged; updating them and remeasuring remains a
-separate comparison. These pins are not claims to track the latest versions.
-This security update and the current comparator controls do not re-date the
-historical observed TCK results above, measured at cA2A
-`806d1147c0bc834ee8aabb698b341c926cd8531e`; they are not results for the updated
-environment.
+The table above is historical evidence at
+`806d1147c0bc834ee8aabb698b341c926cd8531e`, not a result for the current
+environment. The experimental SUT now uses `pyasn1==0.6.5`; #303 did not cover
+this installation path. The [dependency triage](dependency-triage.md) records
+four further security pin updates. Other pins, including `cedarpy` and action
+SHAs, are unchanged. These pins are not claims to track the latest versions.
+
+The workflow checks installed dependency consistency and runs `pip-audit` on
+the SUT environment before executing the experiment. An audit failure stops
+the job; no advisory is ignored. This check does not audit the separate upstream
+TCK environment or establish absence of unknown vulnerabilities. The SUT file
+contains version pins, not a hash lock.
diff --git a/experiments/a2a-tck/dependency-triage.md b/experiments/a2a-tck/dependency-triage.md
new file mode 100644
index 00000000..01c3c248
--- /dev/null
+++ b/experiments/a2a-tck/dependency-triage.md
@@ -0,0 +1,58 @@
+# Experimental SUT dependency triage — 3 November 2026
+
+An installed-environment audit with pip-audit 2.10.1 on Linux/Python 3.12.14
+reproduced 15 advisory findings in four packages from `environment.txt` at
+`3fbd9a3f2a7b3a65a1f2c59651df202614f8d0f1`. No pyasn1 finding remained.
+This is dependency exposure triage, not a demonstrated cA2A exploit.
+
+| Package | Previous pin | Replacement | Findings | Relevant boundary |
+| --- | --- | --- | --- | --- |
+| filelock | 3.32.5 | 4.2.1 | 12 | Local filesystem/lock-directory attacks across several lock implementations; some are Windows-specific. CacheControl's file-cache extra declares this dependency. Shared writable directories are not treated as safe. |
+| msgpack | 1.2.2 | 1.2.3 | 1 | Repeated rejected map keys can leak memory in the C decoder. CacheControl declares msgpack. No attacker-controlled MessagePack path was demonstrated in this experiment. |
+| opentelemetry-api | 1.44.0 | 1.45.1 | 1 | Excessive CPU in malformed inbound tracestate parsing. google-api-core declares it; A2A also exposes optional telemetry dependencies. No remote exploit test was performed. |
+| setuptools | 84.0.0 | 84.1.0 | 1 | Windows legacy wheel installation can escape the destination through namespace metadata. This Linux experiment does not demonstrate that path; grpcio-tools declares setuptools. |
+
+The installed metadata dependency edges above explain why simply deleting these
+pins is not a complete repair. All four pins move to the versions identified as
+fixed by the audit. filelock crosses a major-version boundary, so installation
+consistency and experiment validation are required; this is not a claim of
+universal compatibility. Runtime dependency declarations and upstream TCK's
+independent lock are unchanged.
+
+## Advisory inventory
+
+Filelock findings (all addressed by 4.2.1; GHSA-j8f7-rjxc-mr56 also lists 4.0.9):
+
+- [GHSA-v4x8-3wr5-3wq8](https://github.com/tox-dev/filelock/security/advisories/GHSA-v4x8-3wr5-3wq8)
+- [GHSA-9vhv-jxww-xfm5](https://github.com/tox-dev/filelock/security/advisories/GHSA-9vhv-jxww-xfm5)
+- [GHSA-567q-5qvw-pf92](https://github.com/tox-dev/filelock/security/advisories/GHSA-567q-5qvw-pf92)
+- [GHSA-m462-7rxw-wvpg](https://github.com/tox-dev/filelock/security/advisories/GHSA-m462-7rxw-wvpg)
+- [GHSA-j8f7-rjxc-mr56](https://github.com/tox-dev/filelock/security/advisories/GHSA-j8f7-rjxc-mr56)
+- [GHSA-8mx5-7m5m-r77g](https://github.com/tox-dev/filelock/security/advisories/GHSA-8mx5-7m5m-r77g)
+- [GHSA-69hj-f68j-2879](https://github.com/tox-dev/filelock/security/advisories/GHSA-69hj-f68j-2879)
+- [GHSA-9c4x-gm8v-wgc4](https://github.com/tox-dev/filelock/security/advisories/GHSA-9c4x-gm8v-wgc4)
+- [GHSA-rfpc-qcw5-3pc4](https://github.com/tox-dev/filelock/security/advisories/GHSA-rfpc-qcw5-3pc4)
+- [GHSA-cwqr-hh33-gh44](https://github.com/tox-dev/filelock/security/advisories/GHSA-cwqr-hh33-gh44)
+- [GHSA-fq56-3cx3-fjxp](https://github.com/tox-dev/filelock/security/advisories/GHSA-fq56-3cx3-fjxp)
+- [GHSA-6627-m3xw-93mp](https://github.com/tox-dev/filelock/security/advisories/GHSA-6627-m3xw-93mp)
+
+Other findings:
+
+- msgpack: [GHSA-j586-36cw-2gc2](https://github.com/msgpack/msgpack-python/security/advisories/GHSA-j586-36cw-2gc2)
+- opentelemetry-api: [GHSA-xcq7-p3pf-p88h](https://github.com/open-telemetry/opentelemetry-python/security/advisories/GHSA-xcq7-p3pf-p88h)
+- setuptools: [GHSA-xmj3-9gf7-h52w](https://github.com/pypa/setuptools/security/advisories/GHSA-xmj3-9gf7-h52w)
+
+## Reproduction and limits
+
+Install the current `environment.txt` in a new Python 3.12 virtual environment,
+then run that environment's `python -m pip check` and `python -m pip_audit`.
+The TCK workflow now runs both before the paired experiment. Neither check
+disables findings or exempts these dependencies. Audit results are dated
+observations of the advisory database, not a permanent clean bill of health.
+
+The README's original TCK table remains historical. Current-environment runs
+must retain their own source revision and dependency provenance. This change
+does not establish protected-path certification, Windows execution, a full
+hash lock, or an audit of the separately installed upstream TCK environment.
+
+Prepared with OpenAI Codex.
diff --git a/experiments/a2a-tck/environment.txt b/experiments/a2a-tck/environment.txt
index 1acd3f3d..1a13d96c 100644
--- a/experiments/a2a-tck/environment.txt
+++ b/experiments/a2a-tck/environment.txt
@@ -24,7 +24,7 @@ cryptography==50.0.1
 culsans==0.11.0
 cyclonedx-python-lib==11.12.0
 defusedxml==0.7.1
-filelock==3.32.5
+filelock==4.2.1
 frozenlist==1.8.0
 google-api-core==2.36.0
 google-auth==2.57.1
@@ -44,11 +44,11 @@ librt==0.16.0
 license-expression==30.4.4
 markdown-it-py==4.2.0
 mdurl==0.1.2
-msgpack==1.2.2
+msgpack==1.2.3
 multidict==6.9.1
 mypy==2.4.0
 mypy-extensions==1.1.0
-opentelemetry-api==1.44.0
+opentelemetry-api==1.45.1
 packageurl-python==0.17.6
 packaging==26.3
 pathspec==1.1.1
@@ -80,7 +80,7 @@ rfc8785==0.1.4
 rich==15.0.0
 rpds-py==2026.6.3
 ruff==0.17.1
-setuptools==84.0.0
+setuptools==84.1.0
 sniffio==1.3.1
 sortedcontainers==2.4.0
 sse-starlette==3.4.11

From 2c7b6b3ef94f21b401da5498bd21b363b14e2a1a Mon Sep 17 00:00:00 2001
From: Srinivasa Consultants <78673153+dinakarjs@users.noreply.github.com>
Date: Tue, 3 Nov 2026 19:36:32 +0530
Subject: [PATCH 13/13] docs(tck): record dependency remediation validation

Retain exact source tree and local-to-published commit mapping. Report audit, paired TCK, focused and unit/static checks with limitations.

Signed-off-by: Srinivasa Dinakar Jainti <dinakarjs@gmail.com>
---
 experiments/a2a-tck/dependency-triage.md      | 24 +++++
 .../dependency-validation-2026-11-03.json     | 99 +++++++++++++++++++
 2 files changed, 123 insertions(+)
 create mode 100644 experiments/a2a-tck/dependency-validation-2026-11-03.json

diff --git a/experiments/a2a-tck/dependency-triage.md b/experiments/a2a-tck/dependency-triage.md
index 01c3c248..3b93a2d3 100644
--- a/experiments/a2a-tck/dependency-triage.md
+++ b/experiments/a2a-tck/dependency-triage.md
@@ -55,4 +55,28 @@ must retain their own source revision and dependency provenance. This change
 does not establish protected-path certification, Windows execution, a full
 hash lock, or an audit of the separately installed upstream TCK environment.
 
+## Validation on the updated environment
+
+At local source `29d0d5087ed46ecd17dafd5a945bd76a7386b7f1`, a newly created SUT
+virtual environment installed all 97 pinned packages. `pip check` passed and
+`pip-audit` reported zero known findings. The 15 comparator and 55 bridge/loopback
+tests passed. Both fresh official TCK JSON-RPC MUST runs produced 79 passed,
+156 skipped and 30 deselected. The comparator accepted identical per-test
+outcomes and integer-zero protected-handler counts on both sides. Neither run
+timed out; both recorded clean tracked cA2A source.
+
+The published equivalent source commit is
+`98f4fd69d789509ea81be8aa2a43870d586d91cb`; its tree
+`71ae1b78eacbb3f74b0e680ed1948ab876c136b5` exactly matches the locally
+tested tree. The retained manifests identify the local commit. In a separate
+hash-locked development environment, 796 unit tests passed and two skipped;
+Ruff, mypy (47 files) and configured Bandit passed.
+
+The SDK emitted context-detach and pending-task cleanup diagnostics during the
+runs. This is a passing test/comparator result, not a warning-free execution or
+proof those diagnostics are harmless. Structured revision, environment digest,
+audit and result observations are retained in
+[dependency-validation-2026-11-03.json](dependency-validation-2026-11-03.json).
+These observations do not replace the original historical table.
+
 Prepared with OpenAI Codex.
diff --git a/experiments/a2a-tck/dependency-validation-2026-11-03.json b/experiments/a2a-tck/dependency-validation-2026-11-03.json
new file mode 100644
index 00000000..ebd79a99
--- /dev/null
+++ b/experiments/a2a-tck/dependency-validation-2026-11-03.json
@@ -0,0 +1,99 @@
+{
+  "date": "2026-11-03",
+  "python": "3.12.14",
+  "environment_sha256": "68014f5dcb26a0900549e044c94a76a94b05491583c246bbd7a448bc0237183c",
+  "audit_tool": "pip-audit 2.10.1",
+  "audit_before": [
+    {
+      "package": "filelock",
+      "version": "3.32.5",
+      "advisories": [
+        "CVE-2026-112940",
+        "CVE-2026-112913",
+        "CVE-2026-112907",
+        "CVE-2026-112938",
+        "CVE-2026-112936",
+        "CVE-2026-112910",
+        "CVE-2026-112909",
+        "CVE-2026-112911",
+        "CVE-2026-112939",
+        "CVE-2026-112915",
+        "CVE-2026-112935",
+        "CVE-2026-112908"
+      ]
+    },
+    {
+      "package": "msgpack",
+      "version": "1.2.2",
+      "advisories": [
+        "CVE-2026-114613"
+      ]
+    },
+    {
+      "package": "opentelemetry-api",
+      "version": "1.44.0",
+      "advisories": [
+        "CVE-2026-114603"
+      ]
+    },
+    {
+      "package": "setuptools",
+      "version": "84.0.0",
+      "advisories": [
+        "GHSA-xmj3-9gf7-h52w"
+      ]
+    }
+  ],
+  "audit_after": {
+    "packages": 97,
+    "findings": 0
+  },
+  "focused_tests_passed": 70,
+  "tck": {
+    "baseline": {
+      "ca2a_commit": "29d0d5087ed46ecd17dafd5a945bd76a7386b7f1",
+      "ca2a_tracked_changes": "",
+      "tck_commit": "5daf0144b4a4adbdefb62180739b13c5bd7d8196",
+      "tck_lock_sha256": "7650dafd015617312c49f87bfafaa17e96f6af5d7d73540ce0ef4a2f46dfe404",
+      "runner_sha256": "94c6c29bc669422fee9ca005ae64ee54d5e917bdb9d585c7df195f96c9db6750",
+      "sdk": "1.2.2",
+      "exit_code": 0,
+      "timed_out": false,
+      "protected_handler_invocations": 0,
+      "passed": 79,
+      "skipped": 156,
+      "deselected": 30
+    },
+    "extension": {
+      "ca2a_commit": "29d0d5087ed46ecd17dafd5a945bd76a7386b7f1",
+      "ca2a_tracked_changes": "",
+      "tck_commit": "5daf0144b4a4adbdefb62180739b13c5bd7d8196",
+      "tck_lock_sha256": "7650dafd015617312c49f87bfafaa17e96f6af5d7d73540ce0ef4a2f46dfe404",
+      "runner_sha256": "94c6c29bc669422fee9ca005ae64ee54d5e917bdb9d585c7df195f96c9db6750",
+      "sdk": "1.2.2",
+      "exit_code": 0,
+      "timed_out": false,
+      "protected_handler_invocations": 0,
+      "passed": 79,
+      "skipped": 156,
+      "deselected": 30
+    }
+  },
+  "limits": [
+    "Local Linux software experiment; no protected-path TCK certification",
+    "SUT audit only; upstream TCK environment is separate",
+    "SDK/OpenTelemetry context-detach and pending-task cleanup diagnostics occurred; not a warning-free run"
+  ],
+  "local_source_commit": "29d0d5087ed46ecd17dafd5a945bd76a7386b7f1",
+  "published_equivalent_source_commit": "98f4fd69d789509ea81be8aa2a43870d586d91cb",
+  "source_tree": "71ae1b78eacbb3f74b0e680ed1948ab876c136b5",
+  "publication_note": "The GitHub API-created commit has the identical tested source tree; retained TCK manifests identify the local commit.",
+  "repository_checks": {
+    "environment": "separate hash-locked requirements/dev.txt environment with editable checkout",
+    "unit_passed": 796,
+    "unit_skipped": 2,
+    "ruff": "pass",
+    "mypy": "47 source files pass",
+    "bandit": "pass"
+  }
+}