Create or update a TestRail test run by setting payload.action to 'create' or 'update' with the corresponding project, suite, run, and case details.
Create a new test run or update an existing one in TestRail. Set payload.action to 'create' or 'update' to specify the operation.
| Name | Required | Description | Default |
|---|---|---|---|
| payload | Yes | The mutation payload containing the action (create or update) and the corresponding run attributes |
Changes observed during successful MCP inspections.
v2.2.0v2.1.0v2.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=false, destructiveHint=false and idempotentHint=false, so the safety profile is covered. The description adds only that this is a create/update mutation; it omits update semantics (does an update replace or merge unspecified fields?) and any permission or side-effect notes.
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?
Two short sentences, front-loaded with the operation and followed by the discriminator hint. Nothing redundant or padded.
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 cover safety and the schema fully covers inputs, so the core is adequate. Still, for a non-idempotent mutation the description leaves the update behavior and the divergence in required fields between create and update unexplained, which an agent must infer from the schema.
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%, and the schema itself documents action consts, project_id, run_id, case_ids and name more precisely than the description. The description's single sentence about payload.action adds nothing beyond the structured oneOf discriminator, so the 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?
States a specific verb (create/update) and resource (test run) and names the platform (TestRail). It clearly reads as the write counterpart to the sibling query_run, though it never explicitly contrasts itself with that sibling or with mutate_suite/mutate_section.
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?
It tells the agent that payload.action must be 'create' or 'update', which is a real usage hint for selecting the mode. However, it gives no guidance on when to prefer this tool over query_run, no prerequisites, and no warning about the two actions having different required fields.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.