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

Annotations already declare readOnly/idempotent/openWorld/destructive=false, so the safety profile is covered. The description adds genuine behavior beyond them: the result ordering ('matches ranked exact-ticker first'), which affects how the agent picks among multiple matches. It omits auth or rate-limit context, but the annotation bar is already met.

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?

Three short sentences, front-loaded with the verb and resource, then the prerequisite, then the ordering detail. No filler or repetition of the name or title.

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 two-parameter resolver with no output schema, the description covers what it returns (ranked CIK matches) and why it matters (prerequisite for other EDGAR tools). It could be more complete by noting the shape of a returned match or the default limit, but nothing essential to invoking it correctly is missing.

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%, with both 'query' and 'limit' documented in the schema, so the baseline is 3. The description restates the ticker/name input modes but adds no format or syntax detail beyond what the schema already supplies, and says nothing about 'limit'.

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 (look up) plus the exact resource (a public company's CIK) and both accepted input forms (ticker symbol or company name). It also notes the returned ranking, so an agent can distinguish it from the sibling EDGAR tools that consume a CIK rather than resolve one.

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?

Explicitly says the CIK it returns 'is required for all other EDGAR tools,' which tells the agent to call this first in an EDGAR workflow. It stops short of naming a specific alternative or a when-not condition, so it is strong context but not full routing guidance.

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