fix(mcp): qualify MCP tool names by the resource that owns them - #1106
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🟡 Changes recommended
Sanitized MCP names can bypass TOOL-scope guardrails, and duplicate-name remediation is inaccurate for generic tools.
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🟡 Changes recommended
Qualified MCP names can bypass guardrail matching for names that require sanitization or truncation.
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MCP scopes tool names per server. The Unified Runtime put the raw tool name
into the one flat tool list it hands the model, so two connected MCP servers
exposing the same tool name produced two identically named tools: the provider
rejected the request as a duplicate definition before any LLM call, and the
graph's tool-node map -- keyed by that name -- would have kept only the last
one and routed both servers' calls to it.
The name is now mcp-{resource}-tool-{tool}, matching the format the Temporal
runtime has always used, so traces and eval assertions read the same on either
runtime. Resource names are unique within an agent definition, so the pair is
unique by construction; a pair past the provider's 64-character cap is
truncated and carries a digest of the full pair.
create_tool_node now refuses a duplicate name instead of silently overwriting,
naming both tools and the resources they came from. Since #1072 the provider's
own 400 no longer relays its message, so a collision from any other source
(A2A cards, sanitization) would otherwise surface only as a generic rejection.
Alternatives considered: qualifying only on collision, which would make a
tool's identity depend on which other servers happen to be attached, so adding
a second server would silently rename the first server's tools.
PRODEV-1599
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mcp-{resource}-tool-{tool}, built bymcp_tool_identity(), matching the format the Temporal runtime uses. Resource names are unique within an agent definition, so the pair is unique by construction.create_tool_noderaisesAgentStartupError(INVALID_TOOL_CONFIG)on a duplicate tool name instead of silently keeping the last tool and routing both tools' calls to it. The message names both tools and the resources they came from.call_toolstill uses the raw MCP name, andmetadata["display_name"]still carries it for span titles.Behaviour change: every MCP tool gets a new LLM-facing name, not only colliding ones. Eval sets asserting the old names need updating, which they do not today.
Needs a release before UiPath/uipath-agents-python#763 can bump its pin and merge.
PRODEV-1599