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

The readOnlyHint annotation already conveys the read-only nature. The description adds useful context about what fixtures are and clarifies the project scope, but does not go into additional behavioral details such as pagination or output shape.

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 concise and well-structured, using three focused sentences to cover purpose, fixture definition, scope distinction, and context requirement without unnecessary detail.

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 list tool with fully described parameters and a readOnly annotation, the description is complete enough. It explains the fixture concept, project scope, and alternate tool, though it does not describe the output format or result fields.

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 input schema already fully describes all three parameters with defaults and constraints, so the description adds no additional parameter meaning. Baseline 3 applies because schema description coverage is 100%.

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 tool lists all project-owned fixtures in the active project, with a specific verb and resource. It also distinguishes itself from the organization-level fixture listing tool.

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?

Explicitly instructs to use this tool for project-owned fixtures and to use list_org_fixtures for shared organization fixtures, giving clear when-to-use and when-not-to-use guidance. It also notes the project context requirement.

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