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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false), so the bar is lower, and the description adds a genuine cost signal with 'Spends one lookup' — consistent with idempotentHint=false. It does not describe failure behavior for an unknown or ambiguous vendor, which is the remaining gap.

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 sentences, front-loaded with the payload contents, then the input form and the cost caveat. Nothing is redundant and no sentence fails to earn its place.

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?

With no output schema, the description correctly carries the return-value burden by enumerating the profile sections. It also implies at least one identifier is needed despite zero required parameters. Only the ambiguity/error-path behavior is left unaddressed.

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 every parameter is documented with examples, so the baseline is 3. The description adds that the three identifiers are interchangeable lookup keys and anchors slug to find_vendor's output, which is meaning beyond the schema text.

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?

States a specific verb and resource ('Get one vendor's documentation profile') and then enumerates exactly what the profile contains (DPA coverage, subprocessors, certifications, data locations, transfer safeguards, AI use). This clearly distinguishes it from find_vendor, which is named as the discovery step rather than the retrieval step.

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?

Gives concrete entry conditions: pass the slug from find_vendor, or the vendor's name or domain, which establishes the find_vendor → get_vendor_profile workflow. It does not state when NOT to use it or how it relates to check_portfolio, so it stops short of full alternative routing.

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