Create Project Role

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

The description adds significant behavioral context beyond the annotations: it explicitly states the HTTP 201 return with the new id, the non-idempotent behavior (which aligns with idempotentHint=false but is spelled out), and specific failure modes with common status codes (401 expired token, 403 missing permission, 404 unresolved id). This gives the agent a clear expectation of side effects and error handling.

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 well-structured and appropriately sized: it opens with the core purpose, then covers non-idempotency, error handling, required parameters, and API reference. Each sentence adds useful information without redundancy. The endpoint and error details are efficiently integrated.

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 create operation with two parameters and no output schema, the description covers essential context: the resource created, return id and HTTP status, non-idempotent behavior, common errors, required parameters, and the endpoint. It gives the agent enough to invoke the tool correctly and interpret the response, despite lacking a structured output schema.

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 schema already provides 100% coverage with descriptions for both parameters, so the baseline is 3. The description merely states that project_id and project_role are required, which repeats the schema's 'required' array. It does not add meaning about the structure or contents of project_role (an open object), so it doesn't elevate beyond the schema's baseline.

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 action: 'Create a relationship between a User and a Role in a specified Project.' This is a specific verb and resource, and it distinguishes from siblings like create_company_role (company-level) and list_project_roles by emphasizing the project-scoped user-role relationship. The endpoint and API section further clarify the exact operation.

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 clear context for when to use the tool: to create a project role linking a user and role in a project. It also notes non-idempotency ('calling it again creates another record') and error conditions (401/403/404), which helps the agent understand prerequisites and limitations. However, it does not explicitly name alternative tools (e.g., list_project_roles for reading, delete_project_role for removal), so it lacks explicit 'when-not-to-use' guidance.

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