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

The annotation readOnlyHint=true is consistent with the description, which also mentions the GET /search endpoint. The description adds that results include best-matching symbols with descriptions and types, but it does not disclose pagination, rate limits, or error behavior. It provides some extra context beyond annotations, but not a substantial amount.

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 description is two concise sentences. The first states the core purpose and output, and the second provides the REST endpoint. Every word earns its place, with no filler or repetition.

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?

For a simple two-parameter read-only search tool, the description is sufficiently complete. It states the query semantics and the nature of the return value ('best-matching symbols with descriptions and types'), compensating for the lack of an output schema. It does not address the sibling finnhub_stock_symbols tool, which would make it more complete, but the tool itself is adequately contextualized.

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?

The input schema has 100% coverage with descriptions for both parameters (q and exchange). The description's 'by name or ticker' merely reiterates the existing q description, adding no new semantic information. With high schema coverage, the baseline of 3 applies.

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 searches for stock symbols by name or ticker and returns best-matching results. It names the resource and the action, but does not explicitly distinguish itself from the sibling finnhub_stock_symbols tool, so it falls short of a 5.

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?

The usage is implied: use this when you need to look up stock symbols by name or ticker. However, there is no explicit guidance on when not to use it, nor any mention of alternatives like finnhub_stock_symbols, leaving the agent to infer the choice.

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