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

The readOnlyHint annotation already establishes this is a safe read, so the burden is lighter. The description adds useful context (paginated, and that it maps to GET /models with keywords/page/total query params), but says nothing about result ordering, max page size, or total result counts.

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 tight sentences with the core action and the pagination caveat front-loaded, plus an endpoint mapping. Every clause carries information; nothing is padding.

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 zero-required-parameter read-only list tool with a fully documented schema and annotations covering safety, this is nearly complete. The only gap is the absence of any hint about the shape of the returned model list, which has no output schema to cover it.

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 all three parameters (page, total, keywords) are already documented and the baseline is 3. The description restates the parameter names as API query params but adds no format, default, or constraint detail beyond the schema.

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 (list/search) and resource (fal.ai models in the registry) and notes pagination, so the agent knows exactly what the tool returns. It never names a sibling such as falai_get_model_schema, so the boundary with single-model lookups is left to inference 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 only implied: an agent can infer this is the discovery/browse tool because it lists models, but the description gives no explicit when-to-use, when-not-to-use, or alternative (e.g. use get_model_schema once you know the model id).

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