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

Even with annotations present, the description adds valuable behavioral context: the idempotencyKey requirement and its role in preventing duplicate comments on retry, the plain-text nature and max length, and the security caveat about untrusted CRM field values. This goes well beyond the structured annotations without contradicting them.

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 compact and front-loaded: the core action and constraints come first, followed by the critical idempotency instruction and the security note. Every sentence adds necessary operational value, with no filler or repetition of schema details.

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 mutation tool with five parameters and no output schema, the description covers the essential behavioral requirements: idempotency, size limit, and data-safety handling. It does not mention the return value or explicit error cases, but those are not critical for an agent to invoke the tool correctly.

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 low (20%), but the description compensates by explaining body's type/length and idempotencyKey's fresh-unique-key semantics. It also provides enough context to infer that id identifies the record and objectType identifies the record type, while workspaceId already has schema documentation.

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 action ('Adds a comment'), the resource type (a plain-text comment), and the target ('to one record you may update'). It also adds useful constraints like the 4000-character limit, making the tool's purpose and scope unambiguous relative to siblings like create_activity or list_comments.

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 implies when to use the tool by defining its purpose, and the phrase 'one record you may update' gives a permission-related context. However, it does not explicitly mention alternatives or state when not to use this tool, leaving usage routing mostly to the agent's inference.

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