Set Session Expiry

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

With no annotations provided, the description carries full behavioral disclosure. It explains that expired sessions are excluded from certain tools but not deleted, and that clearing expiry is possible via None. This covers key side effects, though it omits potential error behaviors (e.g., non-existent session).

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 concise and well-structured. It opens with a one-line purpose, follows with behavioral details in paragraph form, and ends with argument descriptions. Every sentence contributes useful information without redundancy.

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 the lack of output schema, the description sufficiently covers return behavior (no deletion, recovery option) and impact on other tools. It could be improved by mentioning error handling for invalid inputs, but overall it is complete for a simple mutation tool.

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?

The schema coverage is 0%, requiring the description to fully explain parameters. It does so effectively: session_id is described as 'ID of the session to update,' and expires_at includes format guidance ('ISO 8601 date string') and the special value None. This significantly adds meaning beyond the schema.

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 'Set or clear an expiry date on a session,' specifying a precise verb and resource. It distinguishes itself from sibling tools like get_session or save_session by focusing solely on expiry management.

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 explains when to use the tool (setting or clearing expiry) and provides context on consequences (exclusion from searches, recovery). It offers clear usage details but does not explicitly exclude alternative scenarios or mention when not to use it.

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