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

Annotations already declare this is a non-read-only, idempotent, non-destructive write, so the safety profile is covered. The description adds genuinely new behavioral context: the value is displayed live to the team on the Live page, which implies public visibility, and it imposes a hard content restriction on what may go into the summary. It does not say how long the status persists or what clears it.

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 tight sentences: the first front-loads purpose and visibility, the second delivers the one non-obvious constraint. No filler, no repetition of the schema.

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 two-parameter, fully documented tool with no output schema, the description covers purpose, visibility, allowed states, and content limits. Only lifecycle details (persistence, whether the status expires or must be cleared) are absent, which is a minor gap given the tool's simplicity.

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% and both parameters are documented in-schema, including the enum values and the 120-character summary limit. The description reinforces the state options and the 'short summary' expectation but adds no syntax or format detail beyond the schema, so the baseline of 3 applies.

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 a concrete action (set what you are doing) and enumerates the exact state values (working, waiting, idle) plus an optional short summary, so the agent knows precisely what the tool writes. It does not explicitly contrast with nearby tools like announce or set_broadcast_subscription, so it stops short of full sibling differentiation.

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 implied rather than stated: it tells you the status is shown live on the Live page, which conveys the context in which to call it, and it gives a content restriction (never include prompt text, file contents or paths). There is no explicit when-not-to-use or named alternative such as a broadcast/announcement tool.

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