Replace exact text

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

The description discloses failure conditions (missing or multiple matches) and the default save behavior, adding context beyond the annotations' destructiveHint. Annotations already note the operation is destructive and not idempotent, so the description builds on that.

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 three short sentences, with the primary purpose first, followed by key edge-case behavior. No filler words or redundant information.

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?

The description omits how the tool interacts with the Neovim buffer system—e.g., whether the file must be open or if it edits the file directly. It also does not describe the return value, leaving some ambiguity for a 5-parameter mutation 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?

The schema covers all five parameters, but the description adds value by explaining that 'save' defaults to true and that 'replace_all' controls multiple-match behavior. This helps agents set parameters correctly.

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 opens with a clear action ('Replace') and identifies the exact resource ('an exact string in a file'). It clearly distinguishes from sibling tools like nvim_edit_lines (line-based) and nvim_insert_lines (insertion).

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 implies this tool is for exact string matching, but it does not explicitly state when to prefer it over siblings like nvim_edit_lines or when not to use it. The behavior around replace_all is mentioned, but no direct comparison to alternatives.

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