How Huginn Works

Huginn runs a continuous agentic loop. You write a prompt, the agent reasons, calls tools (read files, search code, run commands, write files), and repeats until the task is done. You stay in control through per-write approval — you see every diff before it lands on disk.

The agentic loop

You type a request. Huginn:

Reads relevant files and searches your codebase
Reasons about what to change and how
Calls write_file or edit_file tools to apply changes
Pauses before each write and shows you the diff
Continues after your approval — running tests, fixing issues, iterating

No separate planning phase. No explicit “plan then implement” gate. One continuous loop.

Per-write approval

Before any file is written, Huginn interrupts the loop and shows you the diff:

┌─ internal/payment/gateway.go ──────────────────┐
│  + func NewGateway(cfg Config) (*Gateway, error) │
│  +   if cfg.APIKey == "" {                       │
│  +     return nil, errors.New("missing api key") │
│  +   }                                           │
└────────────────────────────────────────────────┘
[y] approve   [n] reject   [A] approve all   [R] reject all

y approve — write this file, continue the loop
n reject — skip this write, agent sees the rejection and can try again
A approve all — approve this and all subsequent writes in the current task
R reject all — reject remaining writes and stop

Controlling how writes are reviewed

Set diff_review_mode in your config:

Value	Behavior
`always`	Pause and show diff before every write (default)
`auto`	Pause only for writes that look risky
`never`	Apply all writes without prompting

Permissions mode

For longer autonomous tasks you can grant broader permissions up front:

huginn --permissions=auto

This is equivalent to diff_review_mode: never — the agent runs to completion without per-write prompts. Use when you trust the task scope and want hands-off execution.

Web UI: artifact review

In the Web UI (huginn tray → localhost:8421), write approval happens through artifact cards. When an agent produces a file change, it appears as a card with Accept, Reject, and Download actions — same approval model, browser-based.