[BUG]: Project ID collision when repos cloned from same source share sessions

[bcheung]

Repos cloned from the same source share the same root commit hash, causing them to share sessions unexpectedly. Opening opencode in either repo shows sessions from both.

Affected workflows

• Cloned templates (e.g., create-react-app, Next.js starters)
• Forks
• Any "clone and change origin" workflow

Reproduction

#!/bin/bash
set -e

WORKDIR=$(mktemp -d)
cd "$WORKDIR"

# Create template repo and clone it twice
mkdir template && cd template
git init -q && echo "template" > README.md && git add . && git commit -qm "init"
cd "$WORKDIR"
git clone -q template clone-a
git clone -q template clone-b

# Run opencode in each
(cd "$WORKDIR/clone-a" && opencode run "respond with only: session from clone-a")
(cd "$WORKDIR/clone-b" && opencode run "respond with only: session from clone-b")

# Verify collision
echo "clone-a project ID: $(cat "$WORKDIR/clone-a/.git/opencode")"
echo "clone-b project ID: $(cat "$WORKDIR/clone-b/.git/opencode")"
# Both are identical - opening opencode in either shows sessions from both

Root cause

Project ID is derived from the first root commit hash:

opencode/packages/opencode/src/project/project.ts

Lines 57 to 72 in 038cff4

	if (!id) {
	const roots = await $`git rev-list --max-parents=0 --all`
	.quiet()
	.nothrow()
	.cwd(worktree)
	.text()
	.then((x) =>
	x
	.split("\n")
	.filter(Boolean)
	.map((x) => x.trim())
	.toSorted(),
	)
	id = roots[0]
	if (id) Bun.file(path.join(git, "opencode")).write(id)
	}

Related

• Desktop app: opening multiple git worktrees from the same repo replaces existing project #5638 - Same root cause but for git worktrees. PR fix: desktop app worktree collision - use separate ID per worktree #5647 fixes worktrees by adding worktree hash, but cloned repos aren't worktrees so they still collide.

Notes on solution

The fix probably needs to be conditional:

• Worktree → Share project ID with main repo (current behavior is correct for this case)
• Git repo (not worktree) → Need deterministic unique ID that doesn't collide across clones. Root commit alone isn't sufficient. Options: include absolute path in hash, or remote origin URL, or generate UUID on first run.
• Not a git repo → Could use absolute path

Key insight: PR #5647 correctly handles worktrees. This issue is specifically about the non-worktree clone scenario.

Side note: worktree caching

In git worktrees, .git is a file (not directory) pointing to .git/worktrees/<name>/. The current cache write to .git/opencode fails silently. Depending on the solution chosen here, this silent failure may cause issues if the fix relies on persisting something to that file.

opencode/packages/opencode/src/project/project.ts

Lines 53 to 56 in 038cff4

	let id = await Bun.file(path.join(git, "opencode"))
	.text()
	.then((x) => x.trim())
	.catch(() => {})

[github-actions]

This issue might be a duplicate of existing issues. Please check:

• Desktop app: opening multiple git worktrees from the same repo replaces existing project #5638: Desktop app: opening multiple git worktrees from the same repo replaces existing project - same root cause (project ID derived from root commit hash)
• Executing run command in worktree reports 'file already exists' error #4656: Executing run command in worktree reports 'file already exists' error - related worktree handling issue mentioned in the "Side note: worktree caching" section

Feel free to ignore if none of these address your specific case.

[rekram1-node]

For worktree stuff did u see the lines of code underneath that? We handle the case that it fails?

[bcheung]

the issue is worktree/.git is a file rather than a folder so the next bit of logic that tries to write the project id also fails silently cause there's no promise handling:

opencode/packages/opencode/src/project/project.ts

Line 71 in 038cff4

if (id) Bun.file(path.join(git, "opencode")).write(id)

this is one line repro script that will emulate what is going on:

cd $(mktemp -d) && git init -q main && git -C main commit --allow-empty -qm "init" && git -C main worktree add ../wt -b t -q && echo ".git is a file:" && cat wt/.git && echo "" && echo "Write fails:" && bun -e "await Bun.file('$(pwd)/wt/.git/opencode').write('x')"

Think what you are looking for is to check and write to /path/to/project/.git/worktrees/my-worktree/opencode