Ensure Lines In File

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

Annotations already indicate destructiveHint=true and idempotentHint=true, which the description does not expand upon. The description adds minimal behavioral context beyond aligning with those annotations. It does not mention SSH dependency or file creation behavior, which are present in the schema.

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, front-loaded sentence with no excessive words. Every word earns its place, providing essential information without being verbose.

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, 3 required, and is destructive, the description is minimal. It does not explain SSH session requirement or the ability to create missing files, though the schema covers these. The output schema exists, reducing the need for return value explanation, but overall completeness is adequate but not thorough.

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 100%, so the schema already describes all parameters. The description adds no additional meaning beyond what the schema provides, such as clarifying the relationship between 'lines' and 'state' or the effect of 'createIfMissing'. Baseline score of 3 applies.

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 the tool ensures specific lines are present or absent, clearly identifying verb and resource. It distinguishes well from sibling tools like fs_write (which writes entire files) and ensure_package (which manages packages).

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 is provided on when to use this tool versus alternatives. For instance, it does not contrast with fs_write for full file content or ensure_package for package management. The description lacks context for appropriate use cases.

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