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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, covering the safety profile. The description adds the return shape and the key trait that "text is a plain-prose summary ... suitable for direct quoting", which is genuine behavioral context. It does not cover error behavior, rate limits, or whether the prose loses structured spec precision.

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 with the resource statement front-loaded and the return contract second; nothing is padded. The leading compatibility clause is slightly jargon-heavy but does earn its place by signalling the intended calling context.

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 one-parameter read tool with full annotation coverage and an output schema, the description is essentially sufficient, and it even restates the return fields. The remaining gap is sibling differentiation against get_listing_detail, which an agent would need in order to choose correctly.

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% and there is a single required id, so the schema does the documentation work. The description only adds the qualifier "Cyclesite listing id", which conveys domain scope but no format or source guidance. Baseline 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?

States a specific verb and resource: "Fetch the full document for one Cyclesite listing id." An agent can tell this is a per-listing full-document retrieval. However, it never distinguishes itself from near-neighbours like get_listing_detail or get_spec_sheet, so the boundary is left to inference.

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?

"OpenAI deep-research / company-knowledge compatibility" implies the context in which this is called (connector/deep-research flows) rather than a normal listing lookup, which is useful. But there is no explicit when-to-use versus get_listing_detail, no exclusions, and no statement of what happens for an invalid or missing id.

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