fix: use flat MCP arguments in tool usage examples - #303
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Tool descriptions served via tools/list showed JSON examples wrapped in
{name, arguments} envelopes. Some models imitated that shape and failed
MCP parameter validation. Examples now match each tool input_schema.
This was referenced Jul 17, 2026
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Summary
Fixes #279 by updating MCP tool description "Usage Example" JSON blocks to show flat argument objects that match each tool's
input_schema, instead of the{"name": ..., "arguments": ...}envelope format.Motivation
Some models (especially smaller ones) read usage examples from
tools/listdescriptions and imitate the envelope shape when calling tools. MCP expects flat arguments, so those calls fail parameter validation with errors likequery: expected string, received undefined.Changes
src/index.ts(20 examples) andsrc/monitor.ts(11 examples)"name"fields inside JSON-schema examples (schema properties, not call wrappers)Tests
Build succeeded locally.
Notes
README and
src/legacy/index.mdstill contain the old envelope format for human docs; they are not served via MCPtools/list. Happy to sync those in a follow-up if desired.