Search WhatsApp messages

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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, covering safety. The description adds behavioral details: it searches semantically ('a paraphrase or another language still hits'), and it mentions 'coverage and freshness' as output indicators. This goes beyond the annotations and informs the agent about search behavior and result quality. No contradiction.

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 sentences with no filler. The core capability is front-loaded ('Find messages by meaning and by words at once'), and the parameter hints are woven in naturally. Every sentence adds value, and the structure is clear and scannable.

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 8 parameters and an output schema, the description covers the main usage scenarios, including hybrid search, exact word matching, and time/person filtering. It mentions output indicators (coverage/freshness). It doesn't explain all params, but the schema handles most. The description is sufficient for an agent to invoke the tool correctly without ambiguity.

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 75% (6 of 8 params have descriptions). The description adds meaning to 'match' by explaining the 'words' mode, and to since/until/from by saying they 'narrow it'. It doesn't explain limit, query, chat_id, account_id, but those are reasonably self-explanatory or covered by schema. Since coverage is slightly below 80%, the description partially compensates, earning a 4.

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 verb 'find' and the resource 'messages', and explains the hybrid semantic+literal search capability. It also mentions scope ('every chat or one'), distinguishing it from read_messages or get_message which are retrieval tools. The purpose is unambiguous and specific.

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 description provides context on when to use the tool: when you need to search by meaning or exact words, and it explains narrowing parameters (since, until, from). However, it doesn't explicitly name alternatives or state when NOT to use it. The guidance is clear but lacks explicit exclusion criteria, so a 4 is appropriate.

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