Run a command

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

Annotations already indicate openWorldHint=true and destructiveHint=true, but the description adds valuable behavioral context: it is not a shell, it returns exit code and output, and a paused environment resumes for it. These details go beyond the annotations and help the agent understand execution semantics.

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 two sentences, front-loaded with the core purpose. Each sentence adds essential information without redundancy, making it highly concise and well-structured.

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?

Given the tool has 5 parameters with nested objects and no output schema, the description covers the primary behavior (command execution, exit code/output) and key usage notes (argv, shell). It lacks detailed parameter explanations but the schema covers timeout_ms, and the annotations cover safety aspects. This is reasonably complete for a command runner tool.

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?

With schema description coverage at only 20%, the description should compensate. It adds meaning to the argv parameter (list form, explicit shell usage) and mentions environment behavior, but does not explain cwd, env, or environment beyond that. The timeout_ms parameter already has a schema description. This is adequate but not comprehensive.

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 explicitly states 'Run one command in an environment and get its exit code and output,' which clearly identifies the verb, resource, and outcome. It also distinguishes itself from a shell, clarifying its scope and differentiating it from sibling tools that manage environments.

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 clear usage instructions: 'pass argv as a list, and ask for a shell explicitly with ["/bin/sh","-lc","…"] if you want one.' It also notes that a paused environment resumes to serve the command, giving practical context. However, it does not explicitly discuss when to use this versus alternatives, though siblings are not direct alternatives.

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