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

With no annotations, the description carries the full burden. It transparently discloses that messages remain stored and readable, are only hidden from the unread inbox unless urgent, and that mute is not a block or closed policy. It does not cover auth requirements or rate limits, but for a mute operation these are less critical. The description provides a clear behavioral model.

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 a single dense sentence that front-loads the purpose and packs in the key behavioral details (storage, inbox exclusion, urgent bypass, not-a-block). It is concise with no filler, though it is long enough that an agent might need to parse it carefully. Still, every clause earns its place.

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?

The description is complete for a mute tool: it explains the effect on inbox and threads, the urgent bypass, and the distinction from blocking. It does not mention return values, but there is no output schema and many tools omit that. It also doesn't explicitly address unmute, but that is a sibling tool. Overall, an agent has enough to call it correctly.

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 both parameters (address and tenant_key) sufficiently. The description does not add extra meaning beyond the schema; it refers to 'urgent: true' which is a property of messages, not parameters. Since the schema covers everything, the baseline of 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 verb 'mute' and the resource 'address', and explains the exact effect: messages are stored but excluded from the inbox, with an urgent bypass. It distinguishes from the sibling 'unmute' and clarifies it is not a block or closed policy, making the tool's purpose unmistakable.

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 implies when to use it: when you want to silence an address while keeping history accessible. It explicitly notes the urgent bypass and states it is not a block, which differentiates it from host.msg.block. However, it does not explicitly say 'use this instead of block when...' or mention when to prefer unmute, leaving some inference to the agent.

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