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

With no annotations, the description carries the full burden, and it does disclose meaningful behavior: persistence on Pro versus a non-mutating preview on Free, plus the fallback pattern for Free users. However, it never says whether it replaces or merges with existing fleet rules, what omitted optional fields do given zero required parameters, or anything about permissions/quota for the Pro write.

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 dense sentences with the core action and field list front-loaded, and the Free-tier caveat correctly placed last. The parenthetical alternative is slightly compressed but earns its space since it prevents a wrong call pattern.

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 5-parameter, all-optional mutation tool with no annotations and no output schema, the description covers purpose, fields, and tier behavior, which is a reasonable baseline. It still omits the update semantics (replace vs merge) that an agent needs before calling with a partial payload.

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 only 20% (only 'fleet' is documented), so the description has to compensate. It does add real semantics for two parameters ('idle_minutes threshold', 'default rates_per_hour by provider') but leaves max_lifetime_minutes and alert_webhook as bare names with no units, format, or expected values, so the gap is only partially closed.

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 and resource ('save the rules ... to a fleet') and enumerates exactly what is persisted: idle_minutes, max_lifetime_minutes, rates_per_hour, and alert_webhook. It also explicitly positions the tool relative to the sibling track_sessions, which is the tool that applies these rules, so the agent can tell them apart without opening either schema.

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 clear tier-conditioned guidance: on Pro it persists the rules, on Free it 'returns a preview ... and saves nothing', with the explicit alternative of passing the same values on each track_sessions call. It lacks an explicit statement of when rules must be set at all (or what happens when a fleet already has rules), so it stops short of full when/when-not coverage.

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