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

With no annotations, the description bears full responsibility. It discloses the similarity metric (Jaccard) and non-market intent, but lacks details on error handling, response format, or deterministic behavior. Adds some value beyond a bare description but is incomplete.

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?

Two sentences: one defining purpose and methodology, one providing usage guidance. No superfluous text; every sentence serves a distinct function. Ideal conciseness.

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?

Given the tool's simplicity (2 params, no output schema), the description covers essential aspects: similarity type, usage prerequisites, and ranking. Minor gaps like return format and error behavior are acceptable for a straightforward tool.

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 coverage is 100%, so baseline is 3. The tool description does not add parameter-specific info beyond what the schema already provides (e.g., the example 'tsmc' and snake_case format are in the schema description for id). No additional semantic enrichment.

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?

The description clearly states the tool finds 'nearest structural neighbours' ranked by Jaccard similarity, contrasting with market or competitive judgments. It distinguishes from siblings like search_companies by specifying that those should be used first for ticker/name resolution.

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?

Explicitly advises using search_companies or resolve_ticker first when only a ticker or approximate name is available, then passing the resolved id. This provides clear when-to-use guidance and excludes the tool for directly handling ambiguous inputs.

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