evac_update_journeyUpdate an existing evacuation journey's name or stages in a fire-simulation project, keeping evacuation routes aligned with changed building layouts or scenarios.
Update an existing evacuation journey
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | Journey ID | |
| name | No | New journey name | |
| stages | No | New stages array ({type, targetId}) |
Changes observed during successful MCP inspections.
v4.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare the full safety profile (readOnly=false, idempotent=true, destructive=false, openWorld=false). The description adds nothing beyond them: it does not say whether the stages array replaces existing stages wholesale or merges, nor what happens to fields omitted from the request.
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 short, front-loaded sentence with no filler. It is efficient, though arguably under-specified rather than genuinely concise given the mutation semantics left unexplained.
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?
Annotations carry the safety profile and the schema fully documents parameters, so the description is not critically deficient. However, for a mutation tool in a dense evac_* family, it omits replacement semantics for stages and any differentiation from evac_update_setup, leaving the agent to infer key behavior.
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 100%, so id, name, and stages are already documented in the schema. The description adds no syntax or semantics beyond that (e.g. replacement behavior for stages), so the baseline of 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?
States a specific verb (update) and resource (evacuation journey), which cleanly separates it from evac_add_journey and evac_remove_journey. It does not, however, differentiate itself from other evac_update_* siblings (setup, agent, stair, waypoint) beyond the resource noun.
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 word 'existing' weakly implies the journey must already be present and that this is a modification rather than a creation, but there is no explicit when-to-use guidance, no prerequisites (e.g. that an id from evac_add_journey is required), and no routing to alternatives.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.