run_javascript

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

With no annotations provided, the description carries the full burden. It discloses 'fixed Node arguments' and 'no shell' but omits side effects (e.g., file system changes), environment, error handling, and execution output format. Minimal behavioral insight beyond basic execution mode.

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 8-word sentence, which is concise but overly terse given the tool has 4 parameters and an output schema. It front-loads the core action but sacrifices completeness.

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?

The tool is moderately complex (4 params, output schema present), yet the description provides no details on return values, prerequisites, or allowed parameter combinations. An agent cannot reliably use this tool without additional context.

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 coverage is 0%, but the description adds no information about any of the four parameters (session_id, entrypoint, arguments, timeout_seconds). The agent must rely solely on the schema for parameter meaning, which is insufficient for correct invocation.

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 verb 'run', the resource 'existing JavaScript file', and key behavioral specifics ('fixed Node arguments', 'no shell'). It effectively distinguishes from sibling tools like create_sandbox and destroy_sandbox.

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 on when to use this tool versus alternatives, such as when the file already exists or the need for a session. No prerequisites or exclusions mentioned. The agent lacks context on the proper usage scenario.

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