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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds that price is returned, which is useful context beyond annotations, but it does not disclose any additional behavioral traits such as pagination via operation_offset or rate limits. It is consistent with the annotations, so no contradiction.

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 a single, tight sentence with no filler. It front-loads the core purpose and the key artifacts returned. Every word earns its place, and it is easy to parse at a glance.

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?

Given that an output schema exists, the description need not explain return structures, and the input schema is fully documented. The combination of description, schema, and annotations is adequate for a read-only retrieval tool. A minor gap is that the description doesn't mention the alternative invocation via operation_query, but this is not critical and is visible in the schema.

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 baseline is 3. The description does not elaborate on the parameters (slug, operation_query, operation_offset), but the schema already provides adequate descriptions for each. It adds no extra meaning beyond what the schema already states, so a mid-score is appropriate.

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 the verb 'Get' and the resource: one endpoint's schema, example, output shape, and price. This specific list of returned artifacts distinguishes it from siblings like search_apis (which searches for endpoints) and estimate_cost (which estimates costs). An agent can immediately understand the tool's scope and differentiate it from alternatives.

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 no guidance on when to use this tool versus siblings such as search_apis or estimate_cost. It does not mention needing a slug from a prior search, nor does it state exclusions or alternatives. Usage context is only implicit in the phrase 'one endpoint', leaving the routing decision to inference.

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