opencode Forgejo Action

A Forgejo Action that runs opencode against a Nomyo (or any OpenAI-compatible) backend, triggered by comments on issues and merge requests.

Mention /opencode or /oc in a comment and opencode reads the thread, executes the requested task, and replies. For "fix" tasks it opens a merge request; for MR comments it commits to the same MR.

Features

Explain an issue

/opencode explain this issue

opencode reads the full thread and replies with an explanation.

Fix an issue

/opencode fix this

opencode creates a branch, implements the change, and opens a merge request.

Update an open MR

Delete the attachment from S3 when the note is removed /oc

opencode commits to the same MR branch.

Review specific code lines

Comment directly on lines in the MR's "Files" tab — opencode receives the file path, line numbers, and diff hunk as context.

/oc add error handling here

Installation

Prerequisites

• A Forgejo instance with Actions enabled.
• A runner that can run Docker containers (the example below uses docker-amd64 with node:lts-bookworm).
• A Forgejo PAT (see scopes below) and a Nomyo API key.

Forgejo PATs

The action uses two Forgejo PATs with split duties — see Security for the rationale. Generate both at Settings → Applications → Manage Access Tokens (Forgejo's write scope inherently grants read on the same resource):

Read PAT — used by the outer action for fetches and read APIs. Never exposed to the opencode subprocess.

Scope	Used for
read:repository	Clone, fetch repo info
read:issue	Read issue/MR thread, comments, files, commits, reviews
read:user	Resolve actor identity (optional, removes log noise)

Push PAT — used only after the agent finishes, for git push and write APIs.

Scope	Used for
write:repository	Push commits and branches
write:issue	Create + update comments, open MRs

If you only have one PAT, give it the write scopes and use it for both — backward compatible.

Secrets

In Repo Settings → Actions → Secrets add:

Secret	Value
FORGEJO_TOKEN	Read PAT (or your single full-access PAT)
FORGEJO_PUSH_TOKEN	Write PAT (omit to share FORGEJO_TOKEN for writes too)
NOMYO_API_KEY	Your Nomyo API key

Workflow file

Add .forgejo/workflows/opencode.yml to the repo where you want opencode to respond. This example targets a Forgejo instance hosted under a subpath (bitfreedom.net/code/); adjust URLs and runs-on to match your setup.

name: opencode
on:
  issue_comment:
    types: [created]
  pull_request_review_comment:
    types: [created]
  pull_request_review:
    types: [submitted]

jobs:
  opencode:
    if: |
      contains(github.event.comment.body, '/oc') ||
      contains(github.event.comment.body, '/opencode') ||
      contains(github.event.review.body, '/oc') ||
      contains(github.event.review.body, '/opencode')
    runs-on: docker-amd64
    container:
      image: node:lts-bookworm
    permissions:
      id-token: write
      contents: write
      pull-requests: write
      issues: write
    steps:
      - name: Install git, curl and Docker
        run: |
          apt-get update -qq
          apt-get install -y -qq git curl unzip docker.io

      - name: Start Docker daemon
        run: |
          dockerd --host=unix:///var/run/docker.sock --iptables=false --dns=8.8.8.8 --dns=8.8.4.4 > /tmp/dockerd.log 2>&1 &
          for i in $(seq 1 30); do
            sleep 2
            docker info > /dev/null 2>&1 && echo "Docker daemon ready" && exit 0
            echo "Waiting for Docker daemon... ($i/30)"
          done
          cat /tmp/dockerd.log
          exit 1

      - name: Checkout repository
        run: |
          git clone --depth=1 --branch "${{ github.ref_name }}" \
            "https://oauth2:${{ github.token }}@bitfreedom.net/code/${{ github.repository }}.git" \
            .

      - name: Fetch action source
        run: |
          git clone --depth=1 --branch v1 \
            "https://oauth2:${{ github.token }}@bitfreedom.net/code/nomyo-ai/actions.git" \
            ./.opencode-action

      - name: Run opencode
        uses: ./.opencode-action
        with:
          nomyo_api_key: ${{ secrets.NOMYO_API_KEY }}
          model: nomyo/unsloth/Qwen3.6-35B-A3B-GGUF:UD-Q4_K_M
          forgejo_api_url: https://bitfreedom.net/code/
          forgejo_token: ${{ secrets.FORGEJO_TOKEN }}
          forgejo_push_token: ${{ secrets.FORGEJO_PUSH_TOKEN }}

Why the manual clone?

act_runner's uses: parser expects https://<host>/<owner>/<repo> — it does not handle a Forgejo instance hosted under a subpath (e.g. bitfreedom.net/code/). For subpath instances, clone the action source into ./.opencode-action and reference it as a local action (uses: ./.opencode-action). If your Forgejo lives at a domain root, you can replace those two steps with uses: <your-host>/nomyo-ai/actions@v1 directly.

Configuration

Input	Required	Default	Description
model	Yes	—	Model in the form provider/model. The provider name becomes a custom opencode provider; the action registers it as an @ai-sdk/openai-compatible provider pointing at nomyo_api_url.
nomyo_api_key	Yes	—	API key for the OpenAI-compatible backend.
nomyo_api_url	No	https://chat.nomyo.ai/api	Base URL of the OpenAI-compatible endpoint. The adapter calls ${baseURL}/chat/completions.
forgejo_api_url	No	https://bitfreedom.net/code/	Forgejo instance base URL.
forgejo_token	No	—	Forgejo PAT used by the outer action for read ops (clone, fetch, read APIs). Stripped from the opencode subprocess env.
forgejo_push_token	No	falls back to forgejo_token	Optional separate write PAT used only after the agent finishes (git push, comment write, MR create).
agent	No	—	Primary agent name to use.
share	No	auto	Share the opencode session (true/false). Defaults to true for public repos.
prompt	No	—	Custom prompt override.
mentions	No	/opencode,/oc	Comma-separated trigger phrases.
variant	No	—	Provider-specific reasoning effort (high, max, minimal, …).

Supported Events

Event	Triggered by	Notes
issue_comment	Comment on an issue or MR	Body must contain a mention phrase
pull_request_review_comment	Comment on a specific line in an MR's Files tab	Receives file path, line number, and diff hunk
pull_request_review	Whole-review submission (Approve / Request changes / Comment) on an MR	Mention must appear in the review body

Architecture

This action is a composite action. On each run it:

1. Installs Bun and the opencode CLI.
2. Runs bun install inside the action source.
3. Registers ${MODEL%/*} as a custom opencode provider via OPENCODE_CONFIG_CONTENT and the API key via OPENCODE_AUTH_CONTENT.
4. Spawns opencode serve locally and talks to it over HTTP (/session/{id}/message).
5. Resolves the event, builds a prompt with thread/diff context, sends it to opencode, and posts the response as a comment (and, for "fix" intents, opens an MR).

There is no compiled dist/ artifact — index.ts is executed directly by Bun.

Security

The agent runs untrusted-ish code (model output executes shell commands, edits files, etc.). The action takes the following defensive measures:

• Two-token model. FORGEJO_TOKEN is read-only, used by the outer process for fetches and read APIs. FORGEJO_PUSH_TOKEN is write-capable and is only loaded into the outer process — it is never placed into the opencode subprocess environment, and it is never written to .git/config.
• Env stripping. When the action spawns opencode serve, the child env is filtered: FORGEJO_TOKEN, FORGEJO_PUSH_TOKEN, and GITHUB_TOKEN are removed. The agent's bash tool inherits opencode's env, so these variables are unreachable from any shell the agent runs.
• Per-command git auth. Credentials for git fetch / git push are passed via git -c http.<host>.extraheader=... on each invocation, not persisted in .git/config. A jailbroken agent cannot git push even with a valid remote.
• Nomyo key exposure (unavoidable). OPENCODE_AUTH_CONTENT (containing the Nomyo API key) must be in opencode's env for the model to work; the agent's bash tool can read it. Treat the Nomyo key as compromised from the agent's perspective and rotate accordingly.

Development

Local test loop (requires Bun and opencode on PATH):

export NOMYO_API_KEY="..."
export NOMYO_API_URL="https://chat.nomyo.ai/api"
export FORGEJO_API_URL="https://bitfreedom.net/code/"
export FORGEJO_TOKEN="..."         # read-scoped PAT
export FORGEJO_PUSH_TOKEN="..."    # optional write-scoped PAT; falls back to FORGEJO_TOKEN
export MODEL="nomyo/unsloth/Qwen3.6-35B-A3B-GGUF:UD-Q4_K_M"
export GITHUB_RUN_ID="test-run"
export GITHUB_RUN_NUMBER="1"
export GITHUB_SERVER_URL="https://bitfreedom.net/code"
export GITHUB_REPOSITORY="owner/repo"
export GITHUB_REF_NAME="main"
export GITHUB_ACTOR="testuser"
export GITHUB_EVENT_NAME="issue_comment"
export GITHUB_EVENT_PATH="/tmp/event.json"

cat > /tmp/event.json <<'EOF'
{
  "repository": { "owner": { "login": "owner" }, "name": "repo", "full_name": "owner/repo" },
  "issue": { "number": 1, "index": 1, "title": "Test", "body": "Test", "user": { "login": "testuser" } },
  "comment": { "id": 1, "body": "/oc explain this", "user": { "login": "testuser" } }
}
EOF

bun install
bun run index.ts

License

MIT