block_contact

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

Disclosures include destructive nature, idempotency, reversibility, notification behavior, and return format. Adds value beyond the given annotations (idempotentHint, destructiveHint) with concrete behavioral details.

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 sentences efficiently convey purpose, behavioral notes, and return format. No filler, front-loaded with main action.

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?

Given the simple tool with one well-documented parameter and comprehensive annotations, the description covers all essential aspects: action, idempotency, reversal, notification, and return value.

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?

With 100% schema description coverage, the schema already thoroughly documents the jid parameter. The tool description does not add extra parameter semantics beyond referencing the return value.

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 tool blocks a contact and specifies the effects: cannot send messages, see last seen/profile photo/status. It distinguishes from sibling unblock_contact by explicitly mentioning reversibility.

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 description provides clear when-to-use context (blocking a contact) and notes reversal via unblock_contact. However, it does not explicitly state when not to use or compare with other tools.

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