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

Annotations already cover readOnly/idempotent/non-destructive/closed-world, so the bar is lower. The description adds real value beyond them: the return shape (citations, scope labels, limitations), the caveat that limitations may not apply to every answer, and the choose_product follow-up flow before making capability claims.

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?

Six tight sentences, front-loaded with purpose and return shape before parameter guidance and the choose_product note. Every sentence carries distinct information with no 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?

With no output schema, the description proactively explains the return contents and the caveat around limitations, and it flags the choose_product decision point. For a read-only research tool with one required param, this is complete enough for correct invocation.

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 0%, so the description must carry parameter meaning. It explains company_id scoping and both evidence_type enum values plus the omission case; only 'limit' and 'question' are left implicit, which is acceptable given 'question' is self-evident and limit is a bounded integer.

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 uses a specific verb ('Retrieve evidence') and states the resource ('plain-English tool question') plus what is returned (citations, scope labels, limitations, source links). It is clearly distinguishable from search/compare/list siblings by its evidence-retrieval framing, though it never explicitly names an alternative.

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 when-to guidance: restrict company_id for a single vendor, choose evidence_type=vendor_documentation vs editorial_guidance, omit for mixed evidence and biographies. It doesn't name sibling tools or say when to prefer them, 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.