list_sessions

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

No annotations are provided, so the description carries the full burden of disclosing behavior. The description implies a read-only listing operation, but it does not explicitly state that it has no side effects, does not modify anything, or what happens in error cases. It is clear in intent but lacks explicit behavioral disclosure.

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 well-structured: the purpose is stated in the first sentence, the return format is clarified in the second, and the usage hint is appended without redundancy. No unnecessary words or vague filler are present.

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 listing tool, the description covers the essential context: what it does, what it returns, and why an agent would use it. Even though an output schema is not shown, the description enumerates the return fields, making the tool self-contained and sufficient for an agent to decide when and how to invoke it.

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?

Both parameters are explained in the description: 'root' is identified as the directory to search with a default to the standard location, and 'limit' is described as the maximum number of sessions. This fully complements the schema, which only provides types and defaults, giving the agent all necessary context.

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 the verb ('List') and the resource ('session transcripts under a root directory'), and it explains the return value (summaries with specific fields). It also conveys its primary use case ('find the session worth analysing'), which distinguishes it from the sibling tools that analyze or report on 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 includes an explicit usage hint ('Use it to find the session worth analysing'), which tells the agent when to invoke this tool. However, it does not explicitly contrast it with the sibling tools (analyze_session, find_loops, cost_report) or mention when not to use it, so it falls slightly short of full guidance.

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