Lookup function in getgc

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint/idempotentHint/destructiveHint, so the safety profile is covered. The description usefully adds a prerequisite (active-client) and cost signal, but its "Signature" line merely restates the schema and it says nothing about result size, truncation, or what "enriched debug metadata" contains.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The purpose sentence is front-loaded and there is no filler prose. But the inline "Signature" block duplicates the input schema verbatim and the "On failure: inspect tool-schema" line offloads rather than informs, slightly diluting structure.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With annotations covering the safety profile and no output schema required, the description is close to adequate. It still leaves gaps for a medium-cost observation tool: no note on result shape, default limits, or how results relate to siblings like list-gc-functions.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the baseline is 3. The description's signature block only repeats parameter names with placeholder types ("mode: any?") and adds no semantics beyond the schema's own enum, defaults, and descriptions.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb ("Search") and resource ("live functions") and clarifies the match dimensions (name/source/constant text) plus the return value ("enriched debug metadata"). It is clearly distinguishable from generic tools, though it never names the very close siblings like find-functions-by-constant, scan-closures-by-name, or list-gc-functions.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides workflow context ("Phase: observe; cost=medium") and a prerequisite ("Requires: active-client"), which implies when the tool fits. However, it offers no explicit when-to-use-vs-alternative routing despite a dense sibling set of function-search tools (scan-closures-by-name, find-functions-by-constant, find-function-xrefs).

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.