invariance_case_event_create

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

Annotations indicate readOnlyHint=false (write operation), destructiveHint=false (non-destructive), and openWorldHint=true (potential side effects). The description adds that this attaches a semantic event, but does not disclose any potential side effects (e.g., triggering monitors, emitting signals, or affecting case state) despite the openWorldHint. It doesn't contradict annotations but fails to elaborate on behavioral traits beyond the basic write action. It does clarify the distinction from raw trace data, which is useful.

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 description is a single, focused sentence that front-loads the core action, provides illustrative examples, and includes usage guidance in the second half. No wasted words; it earns its place.

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 9 parameters, no output schema, and an openWorldHint, the description could be more complete. It explains the core purpose and usage but does not mention what the tool returns, any prerequisites (e.g., the case must exist), or how the event integrates with other case/event tools. It gives enough to get started but leaves gaps for an agent to fully understand the tool's place and effects.

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 78%, so most parameters are documented in the schema. The description does not add meaning for any parameters beyond what the schema provides; it only gives examples for 'type'. It does not compensate for the undocumented parameters (actor_id, actor_type) which lack schema descriptions. Since coverage is high, the baseline is 3, and the description adds marginal value here.

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 clearly states the tool's action: 'Attach a semantic workflow event to a case', with concrete examples of event types. It explicitly distinguishes this from raw execution trace data ('keep raw execution trace data in runs/nodes'), which separates it from related tools like invariance_node_write or invariance_run_*. This is a specific verb+resource with a clear scope.

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 provides explicit guidance: 'Prefer this for meaningful workflow facts; keep raw execution trace data in runs/nodes.' This tells the agent when to use this tool and what to avoid. However, it doesn't explicitly mention alternatives like invariance_workflow_event_create or invariance_signal_emit, so the exclusion list is incomplete. Still, it gives a clear context for use.

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