Documentation
FylloCode is a desktop app for engineering work that uses Coding Agents. It does not replace your IDE, CI/CD, or project management system. It adds a persistent, structured, and traceable governance layer above those tools.
These docs answer three questions:
- Why ordinary Agent sessions are hard to use for long-term engineering collaboration
- How to split one coding task into a reviewable, executable, and archivable workflow
- How to start using FylloCode locally
Recommended Reading Order
To contribute to the project, continue with the Contributing Guide and Developing FylloCode with FylloCode.
Core Concepts
| Concept | Description |
|---|---|
| Task | The entry point of the main path. It can be created locally or synced from an engineering system. |
| Chat | The stage for clarifying intent, inspecting evidence, comparing tradeoffs, converging on a decision with an Agent, and deciding which execution path this change should take. |
| Plan | A session-scoped, lightweight implementation plan for work that needs upfront thinking but doesn't change the behavior contract; escalates to a Proposal the moment a contract change is found. |
| Proposal | A review artifact for contract-changing work, usually containing proposal, design, specs, and tasks. |
| Apply & Archive | The implementation stage inside an approved boundary, followed by archiving decisions, results, spec updates (when applicable), and guideline evolution. |
| guideline | A project's own engineering conventions, self-maintained by the Agent at checkpoints in Chat, Apply, and Archive to stay in sync with the real code. |
| knowledge | Project-level facts shared across tasks and sessions, identified and captured by the Agent using a judgment test (the "flag test"). |
| lineage | A traceable path across the stages of one change, so archived outcomes can inform future tasks. |
| fyllo-action | The structured channel an ACP Agent uses to interact with FylloCode, for task creation, plan review, and knowledge flag/review. |
| fyllo-specs | The built-in MCP server that exposes OpenSpec-based project specifications, Plan, and Proposal workflows. |
| fyllo-cortex | The built-in MCP server that provides guidelines, knowledge, and lineage tools for accumulating project engineering knowledge and tracing design decisions. |