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

Annotations already establish readOnly, idempotent, non-destructive behavior, so the bar is lowered. The description still adds real value beyond them: it warns that a missing row on one page is not proof of absence, tells the agent to paginate, and states the tool neither tests model quality nor spends money. That is genuine operational context, though it omits anything about return shape or when clarification is triggered (the latter is only implied by the schema).

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?

Four short sentences, front-loaded with the core operation, then usage constraint, pagination caveat, and scope exclusion. Every sentence carries distinct information with no repetition of the title or schema.

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 read-only inspection tool with no output schema but a rich 12-parameter input schema, the description covers purpose, usage boundaries, and pagination caveats adequately. It does not describe what a returned declaration row looks like, but the paged nature and clarification behavior are at least gestured at.

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% with 12 well-documented parameters, so the schema carries the semantic load and a 3 is the baseline. The description only echoes 'model and optional rowId' and adds no format, precedence, or interaction detail beyond what the schema already states.

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: reads one provider's paged public declarations, scoped to a model and optional rowId. This is clearly distinguishable from the sibling tools (find_cheapest_api, find_free_credits, resolve_model), though it never names them explicitly. The scope of the operation is unambiguous.

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 explicit when-to-use ('Use only when a detail matters') and when-not-to-use ('not before every recommendation') guidance, plus operational advice to follow pagination rather than treating a missing row as absence. It stops short of naming a specific alternative sibling to use instead for other intents, so it falls short of a 5.

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