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

Annotations already declare readOnly/idempotent/non-open-world, so safety is covered; the description adds genuinely new behavior: results are ranked 'closest matches first', each carries name, argument signature and a one-line summary, and results are returned even when nothing fits. It does not discuss the default result count (limit=6) or how to broaden a weak match set, which is the remaining behavioral gap.

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?

One dense paragraph, front-loaded with scope before examples and routing. Every clause carries information (packs, examples, ranking, no-empty-result caveat, next steps), though the final 'Next:' sentence stacks two alternatives and reads slightly compressed.

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 search tool with a full output schema, the description covers everything an agent needs: corpus size and pack breakdown, how to phrase the query, ranking and result shape, the empty-match caveat, and which sibling to call next. Return-value detail is correctly left to the output schema.

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% and both parameters are documented there, including the 1-50 range and default 6 for limit, so the baseline is 3. The description reinforces the 'plain words' phrasing of query with examples but says nothing about limit and adds no semantics the schema lacks.

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 and resource plus the exact scope: 'Search the 383 finance tools (packs: quant, validation, fundamentals, research, backtest, markets)'. Concrete example queries ('deflated sharpe', 'revenue as of 2019') make the retrieval model unambiguous and clearly separate it from run_tool and describe_tool.

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 routes the agent forward: 'Next: run_tool, or describe_tool if an argument is unclear', naming both siblings with the condition that selects each. It also pre-empts the main misuse path by warning that matches are returned 'even when none fits, so check them', i.e. do not treat an empty-looking result as failure.

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