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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds that each returned run carries a status and maps the operation to the REST endpoint GET /v1/events/{eventId}/runs, which is useful context. It says nothing about pagination, result limits, or behavior when the event triggered no runs, so it remains at the baseline for an annotated tool.

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?

Three short sentences with the core action front-loaded and the endpoint last. The middle sentence is somewhat rhetorical but does orient the agent conceptually; no filler otherwise.

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 single-parameter read-only list tool with no output schema, the description supplies the key return-shape hint (runs plus their statuses) and endpoint mapping. Missing only pagination/volume expectations, which is a minor gap given the tool's simplicity and its readOnlyHint.

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% and the single event_id parameter is documented in the schema itself. The description adds no format, source, or lookup guidance for the id beyond what the schema states, so baseline 3 applies.

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 verb and resource: 'List every function run one event triggered, with each run's status.' That scope ('runs one event triggered') implicitly separates it from siblings like inngest_list_events (all events) and inngest_get_run (a single run). It stops short of naming an alternative explicitly, so it lands just below the top tier.

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 'hop from this event arrived to and here is what it did' framing implies the use case (drill from an event into its downstream runs), but no when-to-use condition, exclusion, or named alternative is given. Usage is inferable rather than stated.

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