Contacts: List Contacts

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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds real value beyond that: page size (15 per page), the auth requirement (User API key via api-access-token header), and the Persian/Arabic-Indic digit handling caveat. It stops short of describing ordering guarantees or total counts, but the additions are substantive.

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 and page size are front-loaded, and the sentences are short. The raw HTTP endpoint and the trailing Persian-text note are slightly tangential for an agent's decision-making but not wasteful enough to hurt much.

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 read-only, idempotent list tool with full annotation coverage and no output schema, the description covers what is needed to call it: scope, page size, auth, and input encoding quirks. Only the relationship to search/filter siblings is left unexplained.

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 description coverage is 100%, so the schema already documents page, sort, and account_id, including the sort enum values. The description only echoes the page size, adding no new meaning to the sort parameter or the accepted digit formats per parameter. Baseline 3 is appropriate.

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 ('List resolved contacts') and defines the key qualifier ('those with an identifier, email or phone number'), which is genuinely useful disambiguation. It does not explicitly name the sibling tools it is not (gapify_search_contacts, gapify_filter_contacts), so an agent still has to infer which list variant to pick.

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?

There is no when-to-use guidance and no mention of the obvious alternatives gapify_search_contacts and gapify_filter_contacts, which sit right next to this tool. The agent must guess whether plain listing, search, or filter is the right entry point.

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