Read Alza account contacts

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

The annotations already declare readOnlyHint and idempotentHint, and the description reinforces read-only behavior. The description adds valuable context beyond annotations by explaining the token requirement and the exact auth steps to follow if no token is loaded, which is genuinely useful behavioral disclosure.

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 front-loaded with the core purpose, then moves to usage, exclusion, and auth instructions in a logical order. Every sentence contributes substantive guidance without unnecessary verbosity.

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 tool with no parameters and an existing output schema, the description covers all essential operational context: what the tool reads, when to use it, a sibling distinction, and the required authentication precondition. Nothing needed to call it correctly is missing.

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 tool has zero parameters and schema coverage is effectively 100%, so no parameter documentation is needed in the description. The description does add related context by mentioning listing and searching behavior, which is reasonable for a no-parameter tool.

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 states a specific verb and resource: 'Read the authenticated user's Alza contact list', plus the exact endpoint. It also explicitly distinguishes itself from the category tree tool by naming list_categories, so an agent can immediately tell this tool apart from related siblings.

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?

It gives clear guidance on when to use the tool ('list or search the account's saved contacts, e.g. for complaint/claim context') and an explicit exclusion with the alternative ('Do not use for the catalog category tree — that is list_categories'). It also provides a prerequisite check and fallback auth flow.

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