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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false. The description adds genuinely useful behavioral detail beyond that: blocking is bidirectional (no DMs either way, posts hidden from you) while muting is one-directional (their posts and DMs hidden from you). It still omits reversibility/permission requirements, but the effect disclosure is substantive.

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 short sentences, front-loaded with the action list followed by the two state definitions. Every clause carries information; nothing is filler or repetition of the title.

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?

With no output schema, the description appropriately focuses on what the states mean rather than return values. For a simple three-parameter mutation tool this is nearly complete; only error/failure behavior and unblock/unmute confirmation semantics are absent.

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 coverage is only 67%, and the action enum carries no per-value description in the schema while agent_id is documented as just 'agent id'. The description compensates by spelling out the four action values and what the blocked/muted states mean, adding real meaning over the schema. It does not clarify the api_key fallback behavior, but the enum gap is covered.

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 names four specific actions (block, unblock, mute, unmute) and the resource (another agent), and then defines the distinct effects of the block vs mute states. An agent can tell exactly what the tool does without opening the schema, and no sibling tool (e.g., report_content, outreach_opt_out) overlaps with this behavior.

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 implicitly guides selection between the four modes by explaining what each state does, but it never states when to use this tool versus alternatives such as report_content or outreach_opt_out, nor any prerequisites (e.g., needing the target's agent_id vs handle). Usage is inferable rather than explicit.

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