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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=false, so the agent knows this is a safe, repeatable read operation. The description adds the tiering scheme and the spam-discard behavior, which is useful additional context. However, it does not describe return format or how sources are evaluated, and with annotations covering the safety profile a 3 is appropriate.

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 that front-loads the main action and then defines the tier taxonomy inline. Every clause earns its place with no redundant restatement of the tool name 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?

The tool is relatively simple (2 params, output schema present), and the description covers purpose, tier definitions, and the spam-discard behavior. It is nearly complete, though it could briefly note how company_domain factors into evaluation or what the output looks like structurally, even though a output schema exists.

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 both parameters (sources and company_domain) are already documented in the input schema. The description does not add any parameter-level detail beyond what the schema provides, so baseline 3 is correct.

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 verb (audit, categorize) and resource (research source domains) and defines the exact tiers used (Tier 1: Official/SEC, Tier 2: Reputable tech press, Tier 3: Aggregators), making it distinguishable from siblings like evidence_validator or github_proofer. An agent can immediately see what this tool does and how sources will be classified.

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 implies when to use it (when you need to audit and categorize research sources and discard spam), but it never names alternatives or exclusions. It does not say whether to use this before or after evidence_validator, nor when not to use it. Usage context is implied rather than explicit.

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