Support MCP tooling hints

[jviotti]

Signed-off-by: Juan Cruz Viotti jv@jviotti.com

[cubic-dev-ai]

1 issue found across 6 files

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[augmentcode]

🤖 Augment PR Summary

Summary: Refactors the MCP implementation to use more explicit data structures and leaner JSON construction.

Changes:

• Simplified tool descriptors to carry a title string instead of a free-form annotations object.
• Reworked MCP initialize handling: precomputed metadata is now stored as a compact array and mapped into MCPServerCapabilities / MCPImplementation.
• Moved/duplicated cursor parsing for resources/list into the enterprise MCP action using std::from_chars.
• Optimized MCP JSON builders by using precomputed property hashes with assign_assume_new.
• Added protocol gating helpers for serverInfo fields (title/description/websiteUrl) around MCP protocol version support.

Notes: Both enterprise and OSS MCP actions were updated to match the new initialize metadata layout and descriptor API.

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[augmentcode]

Review completed. 3 suggestions posted.

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[augmentcode]

src/mcp/mcp.cc:333 Emitting serverInfo.description/serverInfo.websiteUrl can conflict with the current initialize response schema (src/self/v1/schemas/mcp/initialize/response.json), where serverInfo.additionalProperties is false and these fields aren’t listed. If these ever become non-empty in metadata, schema validation/e2e checks may start failing.

Severity: low

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[augmentcode]

src/mcp/mcp.cc:356 instructions is only emitted when non-empty, but the published initialize response schema currently requires an instructions property with minLength: 1. If any caller passes an empty string (or relies on the default argument), responses will stop conforming to that schema.

Severity: medium

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[github-actions]

Benchmark Index (community)

Details

Benchmark suite	Current: e1f7c47	Previous: 15b88fe	Ratio
Add one schema (0 existing)	278 ms	284 ms	0.98
Add one schema (100 existing)	25 ms	27 ms	0.93
Add one schema (1000 existing)	83 ms	88 ms	0.94
Add one schema (10000 existing)	686 ms	846 ms	0.81
Update one schema (1 existing)	19 ms	20 ms	0.95
Update one schema (101 existing)	26 ms	28 ms	0.93
Update one schema (1001 existing)	83 ms	87 ms	0.95
Update one schema (10001 existing)	689 ms	723 ms	0.95
Cached rebuild (1 existing)	6 ms	6 ms	1
Cached rebuild (101 existing)	8 ms	8 ms	1
Cached rebuild (1001 existing)	30 ms	31 ms	0.97
Cached rebuild (10001 existing)	269 ms	281 ms	0.96
Index 100 schemas	112 ms	119 ms	0.94
Index 1000 schemas	870 ms	1133 ms	0.77
Index 10000 schemas	12922 ms	14216 ms	0.91

This comment was automatically generated by workflow using github-action-benchmark.

[github-actions]

Benchmark Index (enterprise)

Details

Benchmark suite	Current: e1f7c47	Previous: 15b88fe	Ratio
Add one schema (0 existing)	289 ms	277 ms	1.04
Add one schema (100 existing)	29 ms	27 ms	1.07
Add one schema (1000 existing)	86 ms	79 ms	1.09
Add one schema (10000 existing)	703 ms	852 ms	0.83
Update one schema (1 existing)	22 ms	20 ms	1.10
Update one schema (101 existing)	28 ms	26 ms	1.08
Update one schema (1001 existing)	86 ms	78 ms	1.10
Update one schema (10001 existing)	707 ms	640 ms	1.10
Cached rebuild (1 existing)	7 ms	6 ms	1.17
Cached rebuild (101 existing)	9 ms	8 ms	1.13
Cached rebuild (1001 existing)	32 ms	27 ms	1.19
Cached rebuild (10001 existing)	275 ms	239 ms	1.15
Index 100 schemas	132 ms	116 ms	1.14
Index 1000 schemas	1047 ms	1182 ms	0.89
Index 10000 schemas	13560 ms	13674 ms	0.99

This comment was automatically generated by workflow using github-action-benchmark.