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

The readOnlyHint annotation already covers the safety profile, and the description adds transparency about what the generated FDD includes (Purpose, Business Context, Data Fields with resolved labels, Business Rules, etc.). It also states the output is 'ready for review and sign-off,' which implies a structured, human-ready deliverable. No contradiction with the annotation; overall the description enriches behavioral understanding.

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 structured and front-loaded with WHEN, but it contains redundancy: the 'WHEN' paragraph and the 'Triggers' paragraph list overlapping examples. The all-caps 'FUNCTIONAL DESIGN DOCUMENT GENERATOR' acts as a title and adds some clutter. It's not overly long, but every sentence doesn't earn its place due to repetition.

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 relatively simple generator with 3 parameters and no output schema, the description covers the essential context: when to use it, what it produces, the sections included, and the alternative for technical docs. It doesn't describe the return format (e.g., markdown vs plain text), but that is a minor gap given the clear output description. Overall the tool is well contextualized.

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 the schema already documents all three parameters adequately. The description adds minimal parameter-level meaning beyond the schema; it hints at 'resolved labels' as part of the generated document but doesn't explain how parameters affect output. Baseline 3 is appropriate because the schema does the heavy lifting.

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 a specific action: generating a Functional Design Document, and lists the exact document types (FDD, functional spec, CdC, cahier des charges). It differentiates itself from get_object_details by warning that it is NOT for technical developer docs. The description also enumerates the sections generated, making the tool's purpose unambiguous.

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 explicit when-to-use guidance with trigger phrases, and an explicit exclusion: 'NOT for developer technical docs -- use get_object_details for that.' This directly routes the agent to the correct sibling tool when the request is technical rather than functional. The trigger list is highly actionable and covers multiple language variants.

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