list_sessions

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

No annotations are provided, so the description bears the full burden. It describes a list operation but does not explicitly state that it is read-only, non-destructive, or what permissions are needed. The condition 'when the CLI exposes them' hints at potential unavailability, but not enough detail.

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?

Two sentences that are efficient and front-loaded. The first states purpose, the second adds a practical usage hint. No redundant information, though it could be slightly more concise.

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 no output schema, the description should indicate what the tool returns (e.g., list of session IDs). It does not. The tool is simple with one parameter, but missing output information reduces completeness for an agent.

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?

Schema description coverage is 100%: the one parameter 'cwd' is already described in the schema. The tool description adds nothing beyond that, so the baseline score of 3 applies.

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 'List available Antigravity CLI conversations for a project directory', identifying verb and resource. It also includes a condition 'when the CLI exposes them', which adds specificity. However, it does not define what a 'session' is, leaving some ambiguity.

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 provides a usage hint by connecting to delegate_task: 'Use session_id with delegate_task to resume.' This implies when to use the tool (to get session_id for resumption). However, it does not explicitly state when not to use it or compare with alternative listing tools like list_workflows or list_pipelines.

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