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

Annotations already declare destructiveHint=true, idempotentHint=true, and readOnlyHint=false, so the safety profile is covered. The description adds a genuinely useful behavioral requirement beyond the annotations — that the request must be SIGNed — though it says nothing about permissions, reversibility, or what signing entails.

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?

Two terse sentences with the core action front-loaded and the signing requirement appended. No waste, though it is arguably under-specified rather than elegantly concise.

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 destructive mutation with no output schema and 0% parameter documentation, the description is too thin. An agent still lacks the signing mechanism, parameter formats, and the effect of unsubscribing on existing subscriptions.

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 0% for both parameters, so the description must carry the burden and does not. It never clarifies acceptable formats for 'channel' (name vs id) or 'agent_id', leaving both required params ambiguous.

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 states a specific verb+resource ('Unsubscribe an agent from a channel') that clearly distinguishes it from the sibling subscribe_channel and from list_channels. It's clear but does not explicitly name the sibling it contrasts with.

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 guidance on when to use this versus alternatives (e.g., list_channels to find a channel, or subscribe_channel). The only contextual hint is 'SIGN the request,' which signals a prerequisite but not usage conditions or exclusions.

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