list_phases

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

Annotations already cover readOnly, idempotent, and non-destructive traits, so the bar is lower. The description adds 'compact' and 'model-phase' but does not disclose additional behavioral details such as whether it returns all phases or only the current one, or whether a model must be open. It adds some context but not rich 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 a single, short sentence ('Return a compact model-phase summary.') with no redundant words or repetition. It is front-loaded and immediately gives the action and object. Every word earns its place.

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 that there are no parameters, a strong annotation set (readOnly, idempotent, non-destructive), and an output schema exists, the description is largely complete for a simple read-only list tool. The phrase 'compact model-phase summary' is slightly ambiguous (e.g., does it list all phases or just a summary of the current one?), but the output schema likely clarifies the return shape, so the description is adequate.

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 has zero parameters, and the schema coverage is 100% (vacuously). The description does not need to explain parameters. Baseline for zero-parameter tools is 4, and the description adds no confusion around parameters.

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 a specific action ('Return') and resource ('compact model-phase summary'), which distinguishes it from mutation tools like create_phase and set_current_phase. However, it does not explicitly differentiate from other list tools (e.g., list_members, list_objects) beyond the resource name, so it's a bit below a perfect score.

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 no guidance on when to use this tool versus alternatives. There is no mention of when to select list_phases over list_members, list_objects, or model_state, nor any exclusions or prerequisites. The name implies the use case, but the description itself offers no usage direction.

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