Get Thread

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explains the thread-assembly algorithm (References/Message-ID grouping, fallback to normalized subject), the matched_by field, chronological ordering, and the cost of include_bodies ('coûte un FETCH complet par message'). This is rich, non-obvious behavior that goes well beyond the schema.

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 compact and front-loaded with the core purpose, then provides the matching algorithm, output ordering, and body-fetch cost. Each sentence contributes unique information and there is no filler or repetition of schema details.

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?

Given an output schema exists and all input parameters are documented, the description covers the remaining essential behavioral context: how threads are matched, how to interpret matched_by, the return ordering, and the performance implication of include_bodies. An agent can call this tool correctly with the information provided.

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 description does not need to re-explain every parameter. It adds meaningful context for include_bodies, describing what it downloads and why it matters for summarization. The other parameters are already fully described in the schema, so the description complements rather than repeats.

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 opens with 'Reconstitue une conversation à partir d'un de ses messages', which names a specific verb and resource: reconstructing a thread from a single message. This clearly differentiates it from siblings like read_email (single message) and search_emails (searching messages), so an agent can identify what the tool does without ambiguity.

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?

It explains the use case for include_bodies ('indispensable pour résumer un échange'), giving practical guidance on when the heavier option is worth using. It does not explicitly name alternative tools or state when not to use get_thread, but the context is clear enough for selecting this tool over siblings.

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