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

readOnlyHint=true already tells the agent this is a safe, non-mutating read, so the safety profile is covered. The description adds the REST endpoint mapping (GET /companies/{id}), which is mildly useful context, but says nothing about behavior such as error/missing-id handling or what the payload contains.

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, front-loaded sentences with no wasted words; the core action leads. The trailing REST-endpoint note contributes little and is the only loosely justified clause.

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 with readOnlyHint annotations, the essential invocation contract is covered. However, with no output schema present, the description gives no hint of the returned company shape or fields, leaving a modest gap for an agent that must reason about the response.

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% – the single 'id' parameter is already documented in the schema, including bounds. The description adds no format, type, or source-of-id guidance beyond what the schema provides, which is the expected baseline.

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 concrete verb+resource ('Get a single company by id') and even names the underlying REST route, so the agent knows exactly what the tool returns. It does not explicitly differentiate itself from copper_search_companies or the other copper_get_* siblings, which would have pushed it to a 5.

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 phrase 'by id' implies you should use this when you already have a company id, but that condition is never stated as guidance, nor is copper_search_companies named as the alternative for lookup-by-attribute. Usage is inferable rather than spelled out.

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