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

Annotations already provide readOnlyHint=false, idempotentHint=true, and destructiveHint=false, so the description doesn't need to restate safety. However, the description adds no behavioral context beyond the hint to read the skill, which is not about tool behavior. For a mutation tool, it could disclose idempotency implications or error cases, but it doesn't, so it falls short of the higher bar.

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 a single, focused sentence that states the core purpose, followed by a direct instruction to read a skill. It's concise and front-loaded with the primary action, with no unnecessary fluff, but it could be clearer about the skill's role.

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 tool is simple (2 params, no output schema, no nested objects), so the description covers the basic action and points to a skill for further details, which is adequate. However, it doesn't clarify what happens after the call (e.g., whether it returns anything) or any side effects, and given the instruction to read a skill, it somewhat relies on external context, making it minimally complete.

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 has 0% description coverage, meaning it only provides types and patterns but no semantic meaning. The description explicitly mentions 'one or more people' and 'a company', which clarifies that personIds is an array (at least one) and companyId is a single ID, adding value beyond the schema. It doesn't explain the ID format, but the patterns are self-explanatory.

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 states the verb 'Associate' and the resource 'one or more people with a company', which aligns with the tool name and title. It is distinct from siblings like merge_companies or update_people, though it doesn't explicitly name them, making it clear but not fully differentiated.

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 mentions 'Before your first call, read the skill: modem_skills(...)', which implies a prerequisite for using the tool, giving some usage guidance. However, it doesn't provide explicit when-to-use or when-not-to-use conditions, nor does it contrast with alternative tools like merge_people or update_companies, so it's only minimally helpful.

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