Block or unblock contacts

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

Annotations already declare destructiveHint=true and idempotentHint=true, so the safety profile is covered. The description adds real context by stating the consequence of block (the contact can no longer message or call) and that confirm must be set, which goes beyond the structured hints.

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 in one sentence, followed by a tight action list where each entry earns its place. No filler or repetition.

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?

No output schema exists, and the description does name the list return shape (number and lid: id), which is useful for a read action. Pagination via limit/cursor is left to the schema, and block/unblock outcome descriptions are minimal, so it is strong but not exhaustive for a 6-parameter multi-action tool.

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 every parameter (limit, cursor, confirm, accountId, contactId) is already documented. The description only restates the confirm:true requirement and does not add syntax or format detail beyond the schema, so the baseline 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 resource (the account's WhatsApp block list) plus a clear verb set, and enumerates the three actions (list/block/unblock) with their effects. An agent can distinguish this from siblings like delete_chat or manage_privacy without opening 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?

The action breakdown gives clear context for what each mode does and when it applies (e.g. blocking stops messages/calls, unblocking reverses it). It stops short of naming alternatives or explicit exclusions, but the routing between the three actions is unambiguous.

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