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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds genuine behavioral context beyond them: unknown values are returned as null, a disclosure accompanies the record, and the agent is told to present links.purchase_url unchanged as the purchase action while crediting source_url.

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 opening clause is well front-loaded, but the middle is one long comma-chained field enumeration that largely restates the output schema. The actionable instructions about links and the disclosure are buried at the end instead of being surfaced.

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 an output schema present, the description need not enumerate return fields, yet it still communicates the two things the schema cannot: null semantics for unknown values and how to render the links. For a single-parameter read tool that is sufficient, though the sibling relationship to check_deal_status is never addressed.

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 itself supplies the format pattern and an example id, so the single parameter is fully documented before the description is read. The description adds no meaning beyond that, which matches the baseline for high-coverage schemas.

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 full public record of one deal" gives a clear resource and scope, and the field enumeration makes the payload concrete. Singular retrieval contrasts implicitly with the list-oriented siblings (search_deals, get_latest_deals), but no sibling is named, so differentiation is inferred rather than stated.

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?

Usage is implied by the required deal_id and by the schema note pointing to search_deals/get_latest_deals as the id source. There is no explicit statement of when to call this versus check_deal_status, nor any prerequisite or failure guidance (e.g., what happens for an unknown or expired id).

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