Get a diagram

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

The readOnlyHint annotation already signals a safe read operation. The description adds the specific return fields but doesn't disclose additional behaviors like error handling or not-found cases. Given annotation coverage, a score of 3 is appropriate.

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, information-dense sentence that front-loads the action and resource. Every word contributes to understanding the tool's purpose and return value.

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 fetch operation, the description covers the essentials: what is fetched and what is returned. No output schema exists, so explaining return values is necessary and done well. It could mention error behavior but that's not critical for this basic get tool.

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 coverage is 100% and the schema already describes diagram_id as 'The diagram id'. The description's 'by id' adds no further semantic detail, so the baseline of 3 applies.

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 ('Fetch'), the resource ('a diagram by id'), and the specific return contents ('title, draw.io XML, and Well-Architected score'). This distinguishes it from sibling tools like get_warnings or get_version, which target different data.

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 clearly implies using this tool to retrieve a diagram's full content by its ID. It doesn't explicitly exclude alternatives or mention when not to use it, but the straightforward purpose and sibling differentiation provide clear context.

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