list_sessions

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

With no annotations, the description bears the burden of behavioral disclosure. It states the tool lists sessions but does not disclose side effects, permissions, or behavior when no sessions exist. However, listing is inherently non-destructive and the simplicity partly compensates.

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 one sentence of five words, perfectly concise and front-loaded. Every word contributes meaning with no unnecessary elaboration.

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 tool has no parameters and an output schema exists, the description is minimally adequate. However, it does not indicate what the output contains (e.g., session IDs, full objects) or handle edge cases like empty index. The output schema compensates somewhat, but the description could be slightly more informative.

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?

No parameters exist, so schema coverage is trivially 100%. Per guidelines, 0 parameters baseline is 4. The description does not need to add parameter info, and it correctly states no arguments are required.

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?

Description uses specific verb 'List' and resource 'every session in the index' clearly stating the tool returns all sessions. The name and action clearly distinguish it from sibling tools like start_session, resume_session, etc., which perform different operations.

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?

No explicit when-to-use or when-not-to-use guidance is provided. However, the tool's purpose is straightforward enough that usage is implied: use when needing a list of all sessions. Sibling list_modes also exists but is differentiated by name.

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