compare_providers

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

Annotations already declare read-only, idempotent, non-destructive, and open-world behavior, so safety is covered. The description adds useful behavioral context beyond that: results are sorted cheapest first and cover every provider on OpenRouter, which helps set expectations for output ordering and completeness.

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?

A single sentence front-loads the core idea ('Same model, different providers') and then enumerates returned fields with the sorting rule at the end. No sentence is wasted and the structure is easy to parse.

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 the low complexity, full schema coverage, rich annotations, and the presence of an output schema, the description supplies everything an agent needs: the comparison scope, returned dimensions, and ordering. Nothing critical is missing for correct invocation.

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 schema fully documents both parameters (model id/name and response_format enum). The description adds no additional parameter syntax or format details beyond what is already structured, so baseline 3 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 states a specific action (compare providers for the same model) and lists the exact dimensions returned (price, context, max output, quantization, uptime), making it easy to distinguish from siblings like find_models or estimate_cost. An agent can tell at a glance that this tool is for provider-level comparison rather than model discovery or cost estimation.

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 phrase 'Same model, different providers' implies the scenario, but there is no explicit guidance on when to prefer this over siblings such as model_price_history or price_changes. Usage is inferable from the purpose but not stated, so it lands at the minimum-viable level.

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