Automated Release Notes

Use a contenox chain as a deterministic CI pipeline: run git log, send commits to an LLM, write RELEASE_NOTES.md — all orchestrated in JSON, no bash glue required.

---

The chain

Save this as .contenox/chain-release-notes.json:

{
    "id": "chain-release-notes",
    "description": "Deterministic pipeline: git log → LLM → RELEASE_NOTES.md",
    "tasks": [
        {
            "id": "get_git_log",
            "description": "Run git log from the tag passed as input to HEAD.",
            "handler": "hook",
            "hook": {
                "name": "local_shell",
                "args": {
                    "command": "git log --oneline \"$(cat)\"..HEAD",
                    "shell": "true"
                }
            },
            "output_template": "{{.Stdout}}",
            "transition": {
                "branches": [{ "operator": "default", "goto": "generate_notes" }]
            }
        },
        {
            "id": "generate_notes",
            "handler": "prompt_to_string",
            "input_var": "get_git_log",
            "system_instruction": "You are a release notes writer. Use ONLY the commits provided. Group under ## Features, ## Bug Fixes, ## Improvements, ## Documentation. Omit empty sections. No preamble.",
            "prompt_template": "Write release notes from ONLY these commits:\n\n{{.get_git_log}}\n\nGroup into markdown sections.",
            "execute_config": {
                "model": "{{var:model}}",
                "provider": "{{var:provider}}"
            },
            "transition": {
                "branches": [{ "operator": "default", "goto": "write_file" }]
            }
        },
        {
            "id": "write_file",
            "handler": "hook",
            "input_var": "generate_notes",
            "hook": {
                "name": "local_shell",
                "args": {
                    "command": "cat > RELEASE_NOTES.md",
                    "shell": "true"
                }
            },
            "transition": {
                "branches": [{ "operator": "default", "goto": "end" }]
            }
        }
    ],
    "token_limit": 32768
}

Run it

Pass the previous release tag as --input. The chain reads from it, not from any state.

contenox run --shell \
  --chain .contenox/chain-release-notes.json \
  --input "v0.2.2"

Output in RELEASE_NOTES.md:

## Improvements
- Improve session implementation
- Refactor input handling: Combine positional args and stdin; resolve default provider

---

How it works

This is a deterministic pipeline — three tasks wired in sequence, no agentic loops:

Step	Handler	What it does
get_git_log	hook → local_shell	Runs git log --oneline "<input>"..HEAD; $(cat) reads the tag from stdin
generate_notes	prompt_to_string	LLM formats the commit log into grouped markdown; {{.get_git_log}} injects the log
write_file	hook → local_shell	Pipes the release notes string into cat > RELEASE_NOTES.md

The key template variable is {{.get_git_log}} — not {{.input}}. In a chain, {{.input}} is always the original chain input (the tag string). Each task's output is available under its task ID.

---

Tips

• Use a stronger model for better grouping:

  contenox run --shell \
    --chain .contenox/chain-release-notes.json \
    --input "v0.2.2" \
    --model gemini-3.1-flash-lite-preview --provider gemini

• Point at a specific tag: --input "v0.1.0" covers everything since that tag
• Upload to GitHub: pipe the output into gh release create v0.2.3 --notes-file RELEASE_NOTES.md