run_tool

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

With no annotations, the description carries the full burden. It transparently discloses the return format (exit code, stdout, stderr, timing), the no-shell argument behavior, and the dry-run support for mutating tools. This is substantial for an execution tool, though it could mention error handling or permissions.

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 concise, front-loaded with the primary purpose, and every sentence contributes useful information. No redundant phrases, and the dry-run tip is valuable without bloating the text.

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 no output schema and no annotations, the description provides necessary return-value information (exit code, stdout, stderr, timing) and context (toolkit root, no shell). It covers the main execution aspects, though it could arguably mention what happens on timeout or failure, which is partially covered by timeout_s in the schema.

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 75% (3/4 params described). The description adds meaning beyond the schema by clarifying that args are an argv list (no shell) and that --dry-run is a preferred flag for mutating tools, which contextualizes the args parameter. This adds value over the schema alone.

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 (execute) and resource (a yala tool), and specifies what it returns (exit code, stdout, stderr, timing). This distinguishes it from sibling tools like find_tools and tool_info, which are for discovery rather than execution.

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 a clear usage guideline: prefer --dry-run for tools with mutates=true. While it does not explicitly name alternatives, it is the only execution tool among siblings, and the dry-run guidance is directly actionable, implying when to use this tool for safe testing first.

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