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

Annotations already establish readOnly/idempotent/non-destructive, and the description adds substantial behavior on top: the call blocks up to wait_seconds, the underlying worker can take minutes to start, an inspection that will never run reports as failed, and a missing legacy endpoint reports as capability unavailable with no emulation fallback. This is exactly the 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?

The core purpose and wait behavior are front-loaded, and each following sentence adds a distinct operational rule (status values, repoll, stop, capability unavailable). It is slightly dense at five clauses but nothing is filler.

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 still conveys the return shape (status enum) and the failure/unavailable cases. Combined with the blocking-wait semantics and the retry/abandon protocol, an agent has everything it needs to invoke and interpret this tool correctly.

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 0%, so the description is the only source of parameter meaning. It explains wait_seconds as a bounded wait with a default and names the two IDs, but gives no hint that IDs are opaque strings or why wait_seconds is capped (max 20), leaving notable gaps for a 3-param tool.

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?

Opens with a specific verb+resource ("Reads one source inspection") and states the exact identifying keys (session_id and probe_id), distinguishing it from the sibling start_source_inspection (which launches) and get_source_probe. The queued/complete/truncated/failed status set is also named, so an agent knows what it is fetching.

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 explicit repoll guidance ("while it is queued, call again with the same ids without asking the person") and a clear stop condition ("After about 10 minutes still queued, stop and tell the person it never started"). It does not route the agent away from a sibling, so it lacks the alternative-naming that a 5 requires, but when/when-not are both covered.

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