getCompanyProfileByCIK

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

Annotations already declare readOnlyHint, idempotentHint and openWorldHint, so the safety and repeatability profile is covered structurally. The description adds value by enumerating the payload contents (stock price, market capitalization, industry), giving a sense of the return shape despite no output schema. It discloses nothing about auth requirements, rate limits, or behavior when the CIK is unknown.

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?

Front-loaded with the core purpose, which is good, but the second sentence largely restates the first ('search for companies using their unique CIK identifier' repeats the CIK lookup) and the vendor/API name is repeated twice. Roughly half the text is marketing padding rather than operational detail.

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 one-parameter read tool with full annotation coverage and no output schema, the description is adequate: it names the key, lists representative returned fields, and makes the lookup mode unambiguous. The remaining gap — CIK formatting expectations — is minor relative to the tool's simplicity.

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 100% for the single 'cik' parameter, so the baseline is 3. The description expands the acronym to 'Central Index Key', which is mild added meaning, but it does not say whether the CIK must be zero-padded to ten digits or accepted as a bare integer — the most likely source of caller error.

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?

States a specific verb and resource ('Retrieve detailed company profile data') plus the exact lookup key ('by CIK'), which distinguishes it from the symbol-based getCompanyProfile without needing to open a schema. It stops short of explicitly naming that sibling, so differentiation is implied by the key rather than declared.

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 only implied: an agent can infer it should call this when it holds a CIK rather than a ticker, and the presence of searchCIK / searchCompaniesByCIK in the sibling list makes that inference reachable. However, no sentence says when to prefer this over getCompanyProfile or searchCompaniesByCIK, and no prerequisites or fallback behavior are stated.

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