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

Annotations already declare readOnly/idempotent/non-destructive, so safety is covered. The description adds real behavioral context: results are ordered newest-to-oldest, paginated, and each hit is returned with its immediate neighbor messages, with full voice transcriptions (voice_transcription/excerpt) and message_kind values. This goes well beyond what annotations provide.

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?

Front-loads the core purpose and then layers scope, transcription fidelity, syntax, context window, and ordering. Each sentence carries information, though it is dense and could be tightened; nothing is padding.

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?

With no output schema, the description carries the burden of explaining returns and does so — found message plus surrounding context, message_kind, transcription fields, ordering, and pagination. Combined with 100% schema coverage of the filters, an agent has everything needed to call it correctly.

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 the baseline is 3, but the description adds genuine meaning for the key 'query' parameter — AND semantics for multiple words, quotes for phrases, and '-word' exclusion — which the schema's terse 'Mots ou expression à chercher' does not convey.

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: full-text search across all messages of the organization, explicitly including voice transcriptions. No sibling is a general message search tool, so this is naturally distinguishable from list_conversations/get_conversation without opening either schema.

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?

Usage is implied (it is a message search tool) and the query syntax is explained, but there is no explicit when-to-use versus alternatives such as ficiel_get_conversation or ficiel_list_conversations, nor any exclusion criteria. Adequate but with a clear gap in routing guidance.

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