Custom REST Read

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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds that the tool issues a GET request and details the path format (no host, no /api/v4 prefix). While this is valuable, it does not discuss potential error responses, rate limiting, or authentication fallback behavior beyond the schema.

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 only three sentences: first defines the core action, second provides usage context with examples, third gives path formatting details, and fourth directs to the write counterpart. Every sentence adds value without redundancy.

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, a description of the return value would be helpful but is not critical since it's a standard API response. The tool is simple, and the combination of annotations, schema, and description covers the essential aspects. A minor gap is the lack of mention of pagination headers or error handling.

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 has 100% coverage with detailed descriptions for all three parameters. The description reinforces this by reiterating the path must start with '/', excluding host and prefix, and that query is optional. It also adds examples. No additional clarification needed.

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 it executes a GET request against GitLab's REST API at /api/v4, explicitly labels it as an 'open-ended escape hatch' for read endpoints not covered by dedicated tools, and provides concrete examples like /projects/:id/repository/files. This distinguishes it from sibling tools, especially the write counterpart execute_rest_write.

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 tells the agent when to use this tool: 'for read endpoints not covered by a dedicated tool.' It also explicitly directs the agent to execute_rest_write for write operations, providing clear guidance on alternatives.

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