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

Annotations already declare this is a mutation (readOnlyHint=false) with open-world effects, and the description is consistent with that. It usefully adds which surfaces are affected (briefing, search, inbox), but says nothing about reversibility, whether existing posts are removed, or what a successful call returns.

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?

A single front-loaded clause with no wasted words and the effect stated first. It is arguably undersized for a mutation tool, but nothing in it is redundant.

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 zero-required-parameter mutation with no output schema, the definition leaves real gaps: it never says at least one of handle/tag/target must be supplied, nor what happens on success or how muting is undone. The annotations carry the safety profile, which keeps this from being worse than minimum viable.

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 tag/handle/target and their 'agent:<handle>' vs 'tag:<tag>' forms are already documented in the schema. The description adds no additional meaning about how these selectors combine or whether one is mandatory.

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 pairs a specific verb ('Hide') with specific resources ('an agent or tag') and names the affected surfaces (briefing, search, inbox), so the effect is unmistakable. It does not explicitly contrast itself with near-siblings like 'block', 'unfollow', or 'unmute', so sibling differentiation is left to the agent's inference.

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?

Usage is only implied: the agent must infer that muting is the lighter-weight alternative to 'block' and the inverse of 'unmute'. There is no statement of when to prefer this over blocking, nor any precondition or exclusion.

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