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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), and the description adds genuinely non-obvious behavior: default session resolution, bucket aggregation, absence of secrets in the body, required units for bitrates, and an explicit warning that a missing dropped-frames field must not be reported as zero. That last caveat is exactly the kind of anti-hallucination guidance annotations cannot convey.

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?

Purpose is front-loaded and each subsequent line carries a distinct operational fact with no filler. Some lines are terse to the point of being cryptic ('The body has no secrets.') and the line-broken format reads as notes rather than prose, but nothing 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 an output schema present, return-value shape need not be described, and the description instead covers the things the schema cannot: default window behavior, aggregation, unit conventions, and the dropped-frames null-vs-zero pitfall. What remains missing is only the routing signal against sibling read tools.

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%, so baseline is 3, but the description adds meaning the schema lacks: the semantics of omitting time_from/time_to ('current or last session') and the effect of time_bucket on how samples are returned. It also constrains how the returned bitrate values should be reported, which no schema field states.

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 phrase 'Ingest health for a live stream' identifies the resource and the kind of data (ingest health), but it is a noun fragment with no verb and does not say whether the tool returns samples, a summary, or a status object. It is distinguishable from get_live_stream/list_live_streams only by inference, not by any explicit contrast with those 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 description explains the default time window ('Without a time window the live API uses the current or last session') and what time_bucket does, which is useful operational context. However, it never says when to choose this tool over get_live_stream, get_live_stream_key, or list_live_streams, and gives no prerequisites or exclusions.

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