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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, so the description doesn't need to repeat those. It adds behavioral context by specifying return states (supported, contradicted, insufficient-evidence, ambiguity/failure) and mentions evidence types (filing/XBRL). This exceeds the baseline without contradicting annotations.

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 redundancy. It front-loads the core purpose, then quickly notes input requirements and output states. Every clause earns its place, making it tightly written and easily scannable.

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 tool's moderate complexity (7 parameters, 1 required) and the existence of an output schema, the description covers essential usage context (input identifiers, output categories, and limitations). It doesn't dive into parameter nuances, but the schema handles that, and the description is sufficient for an agent to decide when and how to invoke this tool.

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?

With 100% schema description coverage, the baseline is 3. The description adds value by clarifying that 'ticker or CIK' are alternative identifiers and that 'claim' is the primary input, which maps directly to the schema's required field. This is a useful clarification beyond the schema's per-field descriptions.

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 function: verify whether a company's official SEC filing supports a specific financial claim. It uses a specific verb ('verify') and resource ('SEC filing'), and distinguishes itself from market-data feeds and investment advice, making its purpose 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 implies usage context (verifying financial claims against SEC filings) and explicitly states what it is not (market-data feed, investment advice), which provides exclusionary guidance. However, it does not explicitly name alternatives or provide when-not-to-use scenarios, though no siblings exist.

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