Description

The Tools documentation lists a built-in tool called patch in the Built-in section. The actual registered tool ID in the source is apply_patch. This causes plugin hooks that check input.tool === "patch" to silently never fire — no error, no warning.

Additionally, the docs don't describe the apply_patch args shape or path format, which differs significantly from edit/write.

Tool name mismatch

Docs say: patch

Source (packages/opencode/src/tool/apply_patch.ts):

export const ApplyPatchTool = Tool.define("apply_patch", { ... })

A plugin author following the docs and writing:

"tool.execute.before": async (input, output) => {
  if (input.tool === "patch") { /* never runs */ }
}

gets silent failure. The correct name is "apply_patch".

apply_patch args shape (undocumented)

apply_patch has a different args shape than edit/write and the docs don't mention it:

// edit / write — filePath is directly available:
output.args.filePath  // absolute path

// apply_patch — no filePath; paths are embedded in patchText as relative paths:
output.args.patchText  // must parse marker lines to extract paths

Marker lines in patchText (paths are relative to project root):

*** Add File: src/new-file.ts
*** Update File: src/existing.ts
*** Move to: src/renamed.ts
*** Delete File: src/obsolete.ts

Resolved internally via path.resolve(Instance.directory, hunk.path).

OpenCode version

1.3.6

Steps to reproduce

1. Read the Tools docs — note tool is listed as patch
2. Write a plugin with if (input.tool === "patch") { ... }
3. Trigger any file edit with a GPT-5-series model
4. Observe: the branch never executes, no error thrown

Verified via:

• GitHub source (dev branch): Tool.define("apply_patch", ...) in src/tool/apply_patch.ts
• Compiled binary string search (v1.3.6)
• Live logging plugin test confirming input.tool values

Operating System

macOS