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

With no annotations, the description carries the full burden. It does disclose that the tool is 'Free' and explains the nature of the evidence (first-party, verified, derived), which gives some transparency about the output. However, it doesn't explicitly state it's a read-only operation, mention any permissions or side effects, or describe the exact response format. This is a reasonable baseline given the tool's simplicity, but more could be added.

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 two sentences with no wasted words. It front-loads the core meaning (how scores are established) and then provides the practical guidance (free, when to call). Every sentence earns its place, and it is structured for quick parsing.

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 simple tool with one required parameter and no output schema, the description covers the essential context: what the tool returns conceptually (evidence breakdown) and when to use it. It might be slightly more helpful to state explicitly that it returns a breakdown, but the three categories imply that. Overall, it's adequate for an agent to decide and call 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 coverage is 50%: the 'context' parameter has a description, while 'slug' does not. The description does not add specific details about the 'slug' parameter beyond what is obvious from its name, nor does it elaborate on 'context' (though the schema already explains it). The description's focus is on the output semantics, not parameter semantics, so it adds only marginal value over 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?

The description clearly states the tool's purpose: explaining how a provider's score was established, with the three evidence categories (first-party, verified, derived). It uses a specific verb and resource. However, it doesn't explicitly name sibling tools that might overlap (e.g., get_provider_rating), so it doesn't strongly differentiate from alternatives, but the purpose 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?

The description gives clear context for when to call it: 'Call this before disputing or quoting a score.' This is an explicit usage directive. It doesn't mention alternatives or when not to use it, but the condition is specific enough for an agent to decide.

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