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

Annotations declare readOnlyHint=true and destructiveHint=false, yet the description says the tool 'record[s] the code' and 'leave[s] the failure for the cron' — i.e., it submits and persists a failure signal that downstream cron behavior depends on. A tool that records state the server later acts on is not read-only, so the description directly contradicts the annotation.

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?

It is short and front-loads the exit-status semantics, but the 0-vs-1-255 rule is stated twice in nearly identical wording ('0 behaves like a ping, 1-255 record the code as a failure' versus '`0` behaves exactly like a plain ping; 1 to 255 record the code and leave the failure for the cron'), so roughly half the text is redundant.

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 only two fully documented parameters and no output schema, the description supplies enough to call the tool correctly: the meaning of the exit code, the shell one-liner, and the resulting failure handling. Only the contrast with its signaling siblings is 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 description coverage is 100%, so the baseline is 3, but the description adds genuine meaning the schema lacks: what 0 means versus 1-255, and that nonzero codes are recorded as failures rather than merely rejected. The schema's 0-255/400 rule is restated, so the gain is real but partial.

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 states a specific action (report a shell exit status) and explains the semantics of the value (0 = ping-like, 1-255 = recorded failure), which is clearer than the bare name. It distinguishes itself semantically from a plain ping, but never names or contrasts the close siblings (signal_fail, ping_ingest, signal_slug), so sibling differentiation is left to inference.

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?

It gives a concrete integration recipe (`curl -fsS $ORIGIN/in/ID/$?` at the end of a script) and explains the intended outcome for each case, including who handles the failure ('leave the failure for the cron'). It does not, however, say when to prefer this over signal_fail or ping_ingest, so the when-not guidance is missing.

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