shell_exec_background

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

With no annotations, the description carries the burden of behavioral disclosure. It clearly indicates that the command runs in the background, requires a job_id, and shares the container session. However, it does not describe what the tool returns immediately (e.g., whether it returns job status or just a success indicator) or address potential side effects beyond process lifetime.

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 extremely concise and well-structured, with clear 'Purpose' and 'Constraints' labels followed by a concrete example. Every sentence adds value: purpose, constraint, related tools, session-sharing note, and example. No redundant or filler content.

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's moderate complexity and the presence of an output schema, the description is largely complete. It covers purpose, required parameter, relationship to sibling tools, and a usage example. The only minor gap is not explaining what the immediate call result looks like, but the output schema presumably covers that.

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. The text states 'Requires job_id' and gives an example with both parameters (command='python3 -m http.server 8000', job_id='http8000'). This clarifies the basic usage but does not explain what job_id represents beyond being a required identifier or any constraints on command formatting.

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 purpose: 'Start a long-running shell command as a background job.' This uses a specific verb ('start'), identifies the resource ('shell command'), and distinguishes it from the sibling 'shell_exec' by specifying background execution and the need for a job_id.

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 explicitly names the companion tools for managing the background job: 'Use shell_check_job to read output and shell_kill_job to stop the process.' It also notes that 'Background jobs share the current container session,' which is important context for usage. This provides clear when-to-use and how-to-manage guidance.

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