[jeffdupont]

Jira: AIC-3573

Problem

wrapToolHandlers turns every NativeTool into a callable tracking stub, so Claude Agents can wire it to the built-in tool. Every other handler keeps any callable. So openai, claude, langchain, litellm and vercel messages, the openai, langchain, litellm and vercel agents handlers, and their native graphs all sent a configured built-in tool (such as web search) to the model as a function tool:

• the provider's built-in tool never turned on;
• the model saw a made-up function that returns nothing;
• a model call to it was still recorded as a tool call.

Change

• isFunctionTool(name, handler) in @launchdarkly/ai-server (utils.ts). It returns false for a NativeTool or its stub (NATIVE_TOOL_KEY) and logs one warning per tool key, then for anything that is not a function. It is listed as - isFunctionTool (handler plumbing) in api-surface/ai-server.txt, like endSpanOnce.
• Every handler and native graph that builds a tool list uses it in place of typeof handler === 'function': 9 handlers and 4 native graphs. Claude Agents is unchanged: it already wires native tools.
• openai-agents and langchain-agents native graphs used to offer every config.tools entry and return '' for a native or missing handler. They now filter on Object.hasOwn plus isFunctionTool. A tool with no handler is no longer offered, like the litellm and vercel graphs. Neither is a name such as constructor inherited from the object; the litellm and vercel graphs and the agents handlers still lack that hasOwn guard, which predates this PR.
• There are no provider built-in mappings (OpenAI web_search and so on) yet. A handler with no built-in skips the tool with a warning and never throws, so adding a mapping later is non-breaking.

Tests

• One test per handler and native graph: a config attaches a function tool and a NativeTool. The provider receives only the function tool, for both the stub and the raw NativeTool, and the second call logs no second warning.
• The openai-agents and langchain-agents native graphs: a node tool with no handler, or named constructor, is not registered.
• Unit tests for isFunctionTool, using the real wrapToolHandlers stub.
• The toLangGraph test that asserted an empty-string tool now asserts that the tool is not registered.
• Control: with the handler sources reverted to main, every new test fails.

Checks run locally: code:check, build, typecheck, api:check, api:surface, test:api-surface, test, lint:pkg.

Python: launchdarkly/python-ai-sdk#248

🤖 Generated with Claude Code

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Note

Overview
Fixes a bug where wrapToolHandlers makes NativeTool handlers look callable, so most provider handlers were advertising configured built-ins (e.g. web search) as function tools instead of using provider natives—leading to useless tool calls and misleading telemetry.

Adds isFunctionTool(name, handler) in @launchdarkly/ai-server: it returns false for a NativeTool or its tracking stub (NATIVE_TOOL_KEY), logs one console warning per tool key, and otherwise requires a real function. Nine message/agent handlers and four native graphs now filter tool lists through this helper instead of typeof handler === 'function' (Claude Agents is unchanged).

OpenAI Agents and LangChain Agents native graphs no longer register every config.tools entry and return '' for native/missing handlers; they only register tools with an own handler that passes isFunctionTool, including skipping names like constructor inherited from the tools object.

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