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

The annotations already indicate readOnlyHint and destructiveHint false, and the description adds useful behavioral context by describing the return structure, the error behavior for no matches, and the limitation that only SEC registrants with a listed ticker are searchable. It does not contradict the annotations and adds meaningful transparency about edge cases.

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 well-organized with clear sections for use cases, examples, and errors. It is slightly repetitive in places (e.g., the return shape is described both in prose and in the Returns line), but every section contributes useful information and the overall length is appropriate for a tool with routing nuances.

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 provides complete context for selecting and calling the tool: when to use it, when to skip it, what it returns, error behavior, search limitations, and examples. Given the sibling tools include related search and EDGAR functions, this context is sufficient for an agent to use the tool correctly without further clarification.

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 already provides full descriptions for both parameters, so the baseline is 3. The description adds value by giving concrete examples of accepted query forms (tickers, name fragments, CIKs), explaining the ranking order, and repeating/illustrating the limit behavior, which goes beyond the schema text.

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 identifies the tool as a search over SEC EDGAR registrants by ticker, company name, or CIK, and specifically notes that it returns the 10-digit zero-padded CIK needed by other edgar_* tools. It also distinguishes itself from search_dart_company for Korean companies.

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 explicitly states when to use the tool ('use when you need a CIK or to disambiguate a company name'), when it can be skipped (exact tickers can go directly to other edgar_* tools), and when not to use it (Korean companies, private companies). It also names the alternative tool for Korean companies, giving clear routing guidance.

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