List contacts

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

Annotations already indicate readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds valuable behavioral context: the endpoint is paginated, returns basic contact info, always falls back to the default profile, and cannot list contacts of other profiles. This goes 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 front-loads the core purpose and keeps the deprecation warning in a separate, clearly marked paragraph. It is mostly efficient, though phrases like 'list of contacts' are repeated and the middle sentence adds only modest information.

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?

Despite having no output schema, the description provides enough context for correct invocation: pagination, filters, deprecation, and the recommended replacement. It does not detail page size or response shape, but for a read-only list endpoint with fully documented optional parameters, the missing details are minor.

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 schema already documents all three parameters. The description confirms that group_uuid and subscription_status act as filters, but it adds little beyond that; page is not mentioned at all. Since the schema carries the semantic weight, a 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?

The description clearly states the operation as 'Get a list of contacts' and specifies the optional filters (group and subscription status), making the resource and action explicit. It also differentiates itself from profile-scoped contact listing by noting the endpoint cannot target a profile and falls back to the default profile.

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 deprecation notice is explicit: this tool cannot target a profile and should be replaced with `GET /api/reach/v1/profiles/{profileUuid}/contacts` instead. This gives clear when-not-to-use guidance and names the alternative, which is exactly what an agent needs to route correctly.

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