Retrieve a specific artifact from a verified browser run, such as video, trace, screenshot, or logs. Choose the run and artifact type to get inline content or a file path for large files.
Fetch one artifact of a run (video, trace, report, screenshot, logs). Small files are returned inline, large ones as a path.
| Name | Required | Description | Default |
|---|---|---|---|
| kind | Yes | ||
| index | No | ||
| run_id | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the behavioral disclosure burden. It adds one useful behavioral trait: small files are returned inline and large files as a path. However, it does not disclose auth requirements, error conditions, or what 'path' means.
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 tight sentences with no fluff. The core purpose is front-loaded, and the size-dependent return behavior 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?
For a tool with no annotations, no output schema, zero parameter descriptions, and an enum of 11 kinds, this description is too thin. An agent cannot reliably determine when to provide 'index', what each kind returns, or how to interpret the returned path.
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 0%, so the description must compensate. It loosely explains the 'kind' parameter with examples, but it does not explain 'run_id' semantics or the purpose of the optional 'index' parameter, which is a significant gap.
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 names a specific verb and resource: 'Fetch one artifact of a run', and gives concrete examples of artifact kinds. It is clear and distinct from sibling tools like get_run or list_runs, though it does not explicitly name those alternatives.
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 no guidance on when to use this tool versus alternatives such as get_run or list_runs. There are no exclusions, prerequisites, or condition-based routing instructions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.