search_messages

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

Describes FTS and lack of stemming, which are key behaviors. However, no details on pagination, sorting, case sensitivity, or permissions. Without annotations, more behavioral context would improve agent understanding.

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?

Extremely concise: two front-loaded sentences covering purpose and filters. No redundant or vague language.

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?

Adquate for a search tool with output schema; covers core functionality and available filters. Lacks details on result ordering, pagination (limit is present but not mentioned), and edge cases. Not fully comprehensive.

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?

Adds value by listing filter parameters (chat_id, sender, from_iso, to_iso) beyond the empty schema descriptions. But does not explain their meaning or format (e.g., date format), and omits the limit parameter entirely. Minimal compensation for 0% schema coverage.

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?

Clearly states 'full-text search over entire history' (FTS) which distinguishes it from sibling tools like draft_reply or list_chats. Specific verb+resource with scope and limitations.

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 notes 'no stemming — try word forms', guiding query formulation. Lists available filters. While it doesn't explicitly state when not to use or name alternatives, the context of siblings makes the use case clear.

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