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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds only the resolution outcome (CIK plus registered name) and says nothing about behavior for unknown tickers, ambiguous matches, or whether the lookup hits a live SEC endpoint. With annotations carrying most of the load, this is adequate but thin.

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?

Two short sentences, with the what-is-returned front-loaded and the usage hint second. No filler, no repetition of the 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 one-parameter resolution tool with no output schema, the description covers input meaning and both return fields, which is nearly everything an agent needs. The only omission is failure/ambiguity handling, which is a minor gap at this complexity.

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% and the schema already documents the single ticker parameter with an AAPL example. The description's "US ticker symbol" merely echoes the schema text and adds no format, case, or exchange nuance. Baseline 3 applies when the schema does the documentation work.

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 pair: resolve a US ticker to an SEC CIK number and registered company name, which is precise about both input and output. The value is distinguishable from heavier siblings like company_snapshot, though it never names a specific alternative by name.

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 sentence "Use this first if you don't already have a CIK" gives clear, actionable when-to-use guidance and implicitly positions it as a prerequisite step for CIK-dependent tools. It stops short of stating when-not to use it or naming the tools that consume a CIK.

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