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

Annotations already flag destructiveHint and openWorldHint, but the description goes further with non-obvious behavior: the call sets no end time (no automatic revert), it overrides existing casts and schedules, and it requires the `screen.edit` and `emergency-override.create` scopes. It also warns against guessing ids. That is exactly the additional context annotations cannot carry.

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 sentences, each load-bearing: effect and scope first, then the irreversibility note, then sourcing/permissions. Front-loaded with the action and impact, no filler or restated 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?

An output schema exists, so return values need no explanation. For a destructive, single-parameter emergency tool the description covers impact, scope, irreversibility, prerequisites, alternatives, and required permissions — everything an agent needs to invoke it safely.

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 100% and the id prefix (etpl_…) is already documented, so baseline is 3. The description adds provenance and safety semantics beyond the schema: the id must come from list_emergency_templates and be operator-confirmed, never guessed. Small but genuine value over the schema.

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?

States a specific verb (fire/trigger) and resource (emergency template) plus the concrete effect: every screen in the template's scope switches to it at once, above any cast or schedule. It explicitly distinguishes itself from the timed-message siblings quick_post and cast_content, so an agent can separate it from near neighbours without opening schemas.

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?

Gives an explicit when (real emergency, immediate takeover), an explicit when-not plus alternative ("For a normal timed message use quick_post or cast_content"), and the prerequisite workflow (fetch the id from list_emergency_templates and confirm scope with the operator). Nothing about tool selection is left to inference.

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