list_merge_request_pipelines

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

Annotations already declare readOnlyHint=true, so the read-only statement is redundant. However, the description adds valuable behavioral details beyond annotations: it is paginated, returns pipeline records or specific GitLab errors (invalid identifiers, missing resources, rate limits), and implies a safe operation. This goes beyond the structured annotations.

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 concise sentences with no filler. The purpose and primary differentiator are front-loaded, and the alternative tool is named up front. Every sentence carries meaningful information.

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 list endpoint with no output schema, the description adequately states what is returned ('pipeline records or GitLab errors') and covers key behaviors (pagination, access requirement). It does not mention ordering or response format details, but for a straightforward list tool, this is sufficient.

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%, so all parameters are already documented in the schema. The description does not add extra semantics for individual parameters beyond what the schema provides. The mention of pagination and project access reinforces existing schema info but doesn't provide new parameter-specific details, so a baseline of 3 is appropriate.

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 ('List') and the resource ('pipelines for a merge request'), and explicitly distinguishes it from the project-wide alternative `list_pipelines`. It is unambiguous about the scope (one MR) and includes pagination, making it easy to select among the many merge-request-related siblings.

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?

It explicitly tells the agent when to use this tool vs. `list_pipelines` ('for project-wide pipeline filtering') and states the prerequisite 'requires project access'. This gives direct, actionable guidance on alternative selection and preconditions.

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