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

Goes beyond the annotations by disclosing that only name is required, type defaults to B, the code is auto-generated, the action notifies no one, requires no confirmation, and is reversible via update_relation. It also names the auth requirement (Cotlet API key with app access), which the annotations do not convey.

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?

Purpose is front-loaded and most sentences carry distinct information (defaults, reversal, duplicate check, auth). The phrasing 'It reaches nobody ... so it does not wait for your OK' is slightly awkward but still informative; little is wasted.

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 an 11-param mutation with no output schema, the description covers required inputs, defaults, reversibility, duplicate avoidance, and the auth requirement. It lacks only info on the return shape or partial-failure behavior, which is minor here.

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% so the baseline is 3. The description adds value beyond the schema by stating which field is required ('Only name is required'), that type defaults to business (B), and that the code is generated when omitted, clarifying default behavior the schema does not spell out.

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 ('Add a customer or supplier') and enumerates the key attributes captured (name, address, email, VAT number, IBAN). This clearly distinguishes it from sibling writes like create_invoice or create_mutation without needing the schema.

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 instructs 'Check list_relations first so you do not create a duplicate' and names update_relation as the undo path. It gives clear pre-conditions but does not state when this tool should NOT be used (e.g. supplier vs customer nuances).

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