run_tool

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

With no annotations, the description must convey behavioral traits, but it only mentions 'ephemeral'. It does not disclose installation side effects, caching, network requirements, or failure modes, which are important for a tool that runs arbitrary packages.

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, well-structured sentence that front-loads the action and resource. It is appropriately concise, though it could include additional context without becoming verbose.

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?

Despite a simple schema and an output schema, the description is minimally complete. It fails to mention how the tool relates to sibling tools, what 'ephemeral' implies for state, or any return behavior, making it insufficient for reliable tool selection.

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?

The schema already describes both parameters ('package' and 'arguments') with 100% coverage, so the description adds no extra parameter meaning. Baseline 3 applies because the schema carries the semantic burden.

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 ('Run') and resource ('an ephemeral tool through uv'), indicating it executes a tool in a temporary context. This differentiates it from sibling commands like 'run' (project execution) and 'run_script', though not 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?

No guidance is provided on when to use this tool versus alternatives such as 'run', 'run_script', or 'tool_install'. The description does not mention exclusions or typical use cases, leaving the agent without decision support.

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