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

Annotations already declare readOnly, idempotent, closed-world and non-destructive, so the safety profile is covered. The description adds real context beyond that: what the payload contains (heartbeat state, tracked vs observed-today coverage, last 24 runs scoped to this workspace) and that coverage is per-workspace and per-day. It stops short of stating freshness/caching or what an unhealthy state looks like, which holds it at 4.

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 sentence that names the primary question (is the job running?) before the supporting details (counts, run history). No filler, no repetition of the title or annotations.

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 must carry the return-shape burden and does so by enumerating heartbeat state, coverage counts, and the last 24 runs. It does not specify timezone/semantics of 'today' or how heartbeat state is encoded, leaving a minor gap for a zero-param read tool.

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?

Zero parameters, so the baseline of 4 applies. The description correctly does not invent parameter behavior and instead spends its words on what the no-arg call returns.

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 noun+scope: whether the hourly observation job is running and how much of this workspace it has covered today, plus heartbeat state and run history. No sibling tool covers scheduler/observation-job health, so it is unambiguously distinct from the keyword/metadata/chart siblings.

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 diagnostic nature of the tool is implied by 'health' and the heartbeat framing, but there is no explicit when-to-use or when-not-to-use guidance. In practice a zero-parameter tool has little room for misuse, which keeps this at minimum-viable rather than low.

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