apply_code_change

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

Annotations already indicate destructiveHint: true, and the description confirms the tool edits source code, aligning with that hint. However, the description lacks additional behavioral context such as whether changes are permanent, affect the original file, or require specific permissions. Given annotations cover the destructive nature, a 3 is appropriate for adding minimal extra context (stopped session).

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 sentence with no wasted words. It is appropriately brief given the context, though it could benefit from a bit more detail without becoming 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?

Despite having an output schema (not shown), the description fails to fully describe the tool's behavior given its complexity and the many sibling tools. It does not explain the expected format of edits, what happens after applying (e.g., does the session continue?), or any limitations. The tool requires deeper guidance for proper use.

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%, and the description provides no information about the parameters 'file' or 'edits'. For 'edits', which is an array of objects with additionalProperties: true, there is no guidance on required structure (e.g., line numbers, new text). This is a critical gap that renders the tool difficult to use 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 clearly states the tool applies source edits to a stopped debug session using Edit-and-Continue. It specifies both the action (apply source edits) and the context (stopped debug session), and distinguishes it from sibling tools like set_variable or evaluate_expression which operate on runtime values rather than source code.

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 mentions the tool is for a stopped debug session, providing clear context for when to use it. It does not explicitly state when not to use alternatives, but the specificity of 'Edit-and-Continue' implies it's for modifying source code during debugging, which is distinct from other tools.

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