session_list

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

With no annotations provided, the description must carry the transparency burden. It discloses that the tool returns both managed session metadata and live tmux sessions, which is meaningful behavioral context. The verb 'List' implies a read-only operation, but the description does not explicitly state safety, side effects, or error behavior. For a zero-parameter list tool, this is adequate.

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, front-loaded sentence containing exactly the necessary information. It has no filler or redundancy, earning a perfect score for conciseness.

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's low complexity (no parameters, no output schema), the description adequately covers what the tool does. It states the contents of the list (metadata and live tmux sessions), though it does not detail the output format. This is sufficient for an agent to invoke the tool correctly in most contexts.

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 tool takes no parameters (0 params, 0 required), so there is nothing for the description to clarify. A baseline score of 4 is appropriate, as the description correctly adds no parameter-specific noise.

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 the specific verb 'List' and clearly names the resource: 'managed sessions (metadata)' plus 'live tmux sessions'. This distinguishes it from sibling tools like session_status or session_context, which operate on individual sessions rather than enumerate all sessions.

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 implies usage (enumerate all sessions) but does not explicitly state when to use this tool versus alternatives, nor does it mention any exclusions. The phrase 'plus any live tmux sessions' hints at scope, but there is no direct guidance like 'for status of a specific session, use session_status instead.'

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