List sessions

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

With no annotations, the description carries the full behavioral burden. It discloses useful traits: the tool returns all saved sessions, orders them by most recent update, and is read-only in nature (implied by 'List'). It does not mention pagination or output format, but for a zero-parameter list operation the key behavior is transparent.

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 a single sentence that front-loads the core action ('List every saved session'), then adds ordering and purpose. Every word earns its place with no redundancy or vague filler.

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 simple zero-parameter tool with no output schema, the description sufficiently covers what the tool does, the ordering, and the motivating use case. It does not explicitly describe the returned fields, but that is a minor gap given the low complexity and clear sibling context.

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 input schema has no parameters and schema description coverage is 100%, so there is no parameter meaning to add. Per the baseline for zero-parameter tools, a score of 4 is appropriate because the description does not need to compensate for any parameter documentation gaps.

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 uses a specific verb and resource ('List every saved session') plus an ordering qualifier ('most recently updated first') and a clear user goal ('so a session can be found again without remembering its id'). This distinguishes it from siblings like get_session, which presumably requires an id, and start_session, which creates a new session.

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 gives clear contextual guidance: use this when you need to locate a session without knowing its id. It does not explicitly name alternatives or state when not to use it, but the 'without remembering its id' phrasing strongly implies that get_session is the alternative when an id is known.

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