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

Annotations already declare readOnlyHint=false and idempotentHint=false, but the description adds the concrete consequence ('calling it twice creates two lists with the same name') and states the return value (the new ID). It stops short of mentioning permissions or whether the name must be unique server-side, which is the only remaining gap.

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?

Three short sentences, front-loaded with the action and result, then the duplicate-risk caveat, then the follow-up path. No sentence is filler.

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 creation tool with no output schema, the description covers the action, the returned ID, the duplicate pitfall, and next steps. Only minor items like error behavior (e.g., duplicate-name rejection) or auth requirements are absent.

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 single parameter is fully documented in the schema ('List name, 1–200 characters'), and the description adds no format or constraint detail beyond that. With 100% schema coverage, the schema does the work and the baseline of 3 applies.

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 ('Create a new, empty contact list') plus the result ('return it with its new ID'). This clearly separates it from directiq_rename_list, directiq_delete_list, and directiq_get_list 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 warns to check directiq_list_lists first because calling twice creates duplicates, and names the follow-up tools (directiq_upsert_contact, directiq_add_contact_to_list) for populating the list. Both the when and the next-step alternatives are spelled out.

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