eventarc_replay_event

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

With no annotations, the description carries the full burden and does disclose the key behavioral trait: a *new* event is produced with origin 'replay', and the tool reports the resulting deliveries. It does not say whether matched functions actually execute as a side effect, whether replay is idempotent, or what permissions are required.

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 with the action, target, and result stated up front; the parenthetical '(a new event, origin replay)' adds semantics rather than 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?

A side-effecting mutation with no annotations and no output schema needs the description to explain consequences and return shape. 'Report the new deliveries' hints at the response, but the effect on matched functions and any irreversibility are left unstated.

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 schema itself explains the subtle id distinction (Eventarc id vs CloudEvent id) and the keepId default. The description adds no parameter-level meaning beyond what the schema already provides, so the baseline 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?

States a specific verb chain (re-deliver a received event to matching functions) plus the distinguishing qualifier that this is a replay of an existing event rather than a publish. An agent can separate it from eventarc_publish and eventarc_list_events, though no sibling is named explicitly.

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?

Usage is only implied: you call it when you want to re-deliver an event you previously received. There is no explicit when/when-not guidance and no pointer to eventarc_publish or functions_replay_call as alternatives, both of which could be confused with re-running a function against an event.

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