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

Without annotations, the description carries the full behavioral burden and discloses key traits: returned fields, 'newest first' ordering, optional filters, and the payment model ($0.003 USDC per call via x402 on Base). It does not cover error handling or rate limits, but it provides substantial operational context beyond the schema.

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 front-loaded with the core purpose and packs useful details (returned fields, example request, pricing) into two sentences. It is dense but every element serves a clear function, with no redundant filler.

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 description lists the returned fields and pricing, which compensates for the lack of an output schema, but it omits a crucial requirement: although only 'concept' is required, the user must supply either 'ticker' or 'cik' to identify the company. This gap could cause an agent to invoke the tool without a company identifier.

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?

The schema has 100% description coverage for all six parameters, so the baseline is 3. The description adds an example body and mentions optional form and unit filters, but it does not deepen semantic understanding beyond what the schema already documents.

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 that it returns values of one XBRL concept for a US company, listing the specific fields returned. It does not explicitly differentiate itself from sibling tools like edgar_facts_query or edgar_financials, leaving some ambiguity about which EDGAR tool to choose.

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 implied by 'Values of one XBRL concept' and the example body, but there is no explicit guidance on when to use this tool versus alternatives such as edgar_facts_query. Optional filters (form, unit) and the limit are mentioned but no exclusions or prerequisites are stated.

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