install_r_packages

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

The description adds the key behavioral detail that only allowlisted packages are installed, which is beyond the annotations. However, it does not disclose side effects (e.g., overwriting existing packages, dependency installation) or error handling. The annotations already indicate it is not read-only (readOnlyHint=false), so no contradiction.

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 is front-loaded with the core action and constraint. Every word is meaningful with no redundancy.

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?

For a tool that installs packages, the description omits important context such as behavior when a package is not allowlisted, dependency resolution, or response format details (though output schema exists). It is minimally adequate but could be more complete.

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 input schema has high description coverage (all parameters have descriptions in the schema), so the tool description does not need to repeat them. The description adds no new parameter information beyond the schema, so a baseline of 3 is appropriate.

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 specific action (install), the resource (allowlisted R packages), and the distinguishing feature (only allowlisted, returns structured results). This effectively differentiates it from sibling tools like run_r_script.

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 no guidance on when to use this tool versus alternatives (e.g., run_r_script). It does not mention prerequisites, scenarios where installation fails, or when to prefer other tools.

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