Forge
Your coding agent needs a second opinion.
Forge is the engineering reasoning companion beside your coding agent.
It can inspect a repository, challenge plans and fixes, keep durable
conversations, and produce implementation instructions for Cursor, Claude,
Codex, or another coding agent.
Forge is not another coding agent. It does not replace those tools or
write application source.
Preview 0.2.1. A product of DevFoundry.
Product site: forgedev.tools
What Forge is
- Engineering reasoning beside your coding agent
- Ask — architecture, debugging, risk, and implementation questions
- Review — a second opinion on a proposal from another agent
- Forge Projects — engineering knowledge workspaces for conversations.
A project is not a repository, a VS Code workspace, or a folder. Projects
can exist with no repository open. A local folder can be linked to a project.
- Conversations — durable threads on this machine, including threads that
are not in a project yet (Unassigned)
- A sidebar navigator for everyday browsing, and a larger Conversations
organizer for folders, tags, pin, archive, rename, move, and delete
- Attachments — images, PDFs, and supported text or source files you
choose to send with a message
- Copy as Instructions for coding-agent handoff
- Project Memory under
.forge/memory.json when a folder is open
- Your own OpenAI or Anthropic API key (BYOK), stored separately in VS Code Secret Storage
Tags belong to one Forge Project. Moving a conversation to another project,
or to Unassigned, removes those tags. Moving it back does not restore them.
What Forge is not
- Not a replacement for Cursor, Claude Code, Codex, or other coding agents
- Not an editor that writes application source
- Not hosted Forge AI (no DevFoundry-billed model in this release)
- Not telemetry, cloud sync, or a Forge account
- Not a remote-repository client, and not a separate desktop, mobile, or web app
- Not a store of Project Notes or Findings. Save Finding still writes
.forge/memory.json
- Not an attachment library. There is no screen for cleaning up stored files
Requirements
- Visual Studio Code 1.85+ or a compatible Cursor build
- An OpenAI API key, or an Anthropic API key, for the provider you select.
New threads start from
forge.reasoning.provider and forge.reasoning.model
(defaults: OpenAI, gpt-5). A thread keeps the model you choose.
Forge can reason with no folder open. Repository tools, .forge/ Project
Memory, and legacy planning need a workspace folder. Those repository
workflows use the first workspace folder.
A ChatGPT or Claude subscription does not provide API usage for Forge.
Each provider bills API usage to your API account. Forge does not read
Claude Code or Claude.ai login credentials.
Install
Forge 0.2.1 is the same extension (devfoundry.forge-extension) across
official DevFoundry-authorized channels. Those channels may include:
- a direct VSIX from forgedev.tools
- Visual Studio Marketplace
- Open VSX Registry
Look for Forge by DevFoundry from publisher DevFoundry. In the
editor, the product still appears as Forge.
Getting started: forgedev.tools/docs/getting-started
From the Extensions view
When a gallery listing is available for your editor, open the Extensions
view, search for Forge by DevFoundry, and install
devfoundry.forge-extension.
From a VSIX (VS Code or Cursor)
- Download
forge-extension-0.2.1.vsix from forgedev.tools.
- Command Palette → Extensions: Install from VSIX…
(or Extensions view →
… → Install from VSIX…).
- Select the downloaded file.
- Reload the window if prompted.
- Forge appears in the activity bar. Open a folder when you want
repository tools.
CLI (optional):
code --install-extension forge-extension-0.2.1.vsix
If you already installed Forge 0.1.0, 0.1.1, 0.1.2, or 0.1.3, installing 0.2.1 in place keeps
the same extension ID, API key, settings, and Project Memory.
OpenAI API key
- Create an API key in your OpenAI account (not a ChatGPT password).
- In the Forge header, click the key icon, or run Forge: Set OpenAI API Key.
- Paste the key. It is stored in VS Code Secret Storage, not in
.forge/
or settings.json. Forge never displays the stored key.
Remove it with Forge: Clear OpenAI API Key.
Anthropic API key
- Create an API key in your Anthropic account (not a Claude.ai or Claude Code login).
- Run Forge: Set Anthropic API Key, or choose an Anthropic model and use the key icon.
- The key is stored separately as
forge.anthropic.apiKey in VS Code Secret Storage.
Remove it with Forge: Clear Anthropic API Key.
The model control in the composer lists Claude Opus 5, Claude Sonnet 5, and
Claude Sonnet 4.6, plus the configured OpenAI model. Supported Claude models
also show Effort; Default leaves Anthropic’s own effort setting in place.
Choosing another provider while a thread is already bound starts a new
conversation. The previous thread stays in Conversations. Anthropic threads
continue from the local transcript. OpenAI threads can also use OpenAI’s
Conversations API.
Ask, Review, and attachments
- Ask — questions about architecture, debugging, or the open repository.
Enter sends; Shift+Enter inserts a newline. While Forge is processing,
Stop cancels the current turn. Workspace paths in an answer open in the
editor, including
path:line and path:line:column. Right-click a path
for more actions.
- Review — paste a proposal, or use Choose source… (editor, clipboard, file).
After review starts, the composer returns to Ask for follow-up.
- Attachments — add images, PDFs, or supported text and source files
from the file picker, by dropping files on the composer, or by pasting an
image. They stay local until you send the message. That send includes the
selected files for the provider on the thread. Not every model accepts
images or PDFs.
Type / at the start of the composer for local shortcuts: /new,
/conversations, /help, /model, /usage, and /key. They do not call
the reasoning model.
Copy as Instructions copies the ## Instructions for the coding agent block
when Forge produced one. Save Finding writes a durable note to
.forge/memory.json. Previous threads stay in Conversations. Use the header
control to browse them, and the organizer when you want to manage projects
and folders. Help in the Forge sidebar covers these workflows and shows
local usage counts.
Project Memory
Save Finding and related legacy workflows write under the open folder’s
.forge/ directory. That folder is local workspace data. It is not the
store for Forge Projects or Conversations. Uninstalling Forge does not
delete it.
Forge Projects, conversations, folders, tags, and attachments live in a
Forge-owned directory on this machine, outside editor extension storage:
- macOS:
~/Library/Application Support/Forge/knowledge
- Windows:
%APPDATA%\Forge\knowledge
- Linux:
$XDG_DATA_HOME/forge/knowledge, or ~/.local/share/forge/knowledge
Uninstalling the extension does not delete that directory. Deleting Forge
knowledge is a separate intentional action. There is no screen for that yet.
Forge may read an older editor copy, or an older workspace transcript, while
moving history. It does not replace a knowledge directory that already exists.
Privacy
When you Ask or Review, Forge may send chat, repository-derived context,
and any files included with that message to the selected provider using
that provider’s key. Repository tools do not read .env* contents. A file
you attach and send, including an .env* file you chose, can be sent.
Forge does not send telemetry, prompts, attachments, or source to
DevFoundry. Usage counts in Help stay on this machine. There is no cloud
sync.
See forgedev.tools/privacy.
Preview limitations
- Legacy planning and
.forge/ memory use the first workspace folder
- Forge can reason with no folder open. One open folder can supply repository tools. With several folders open, those tools run only when exactly one folder is linked to the focused project
- Not every model accepts every attachment type
- Each model request can time out; the selected provider must allow the model
- Conversations and attachments stay in the Forge knowledge directory on this machine, not in the repository
- Uninstall leaves that knowledge directory and
.forge/ on disk. Deleting Forge knowledge is separate from uninstalling the extension
- No supported multi-root mode, remote repository access, or cloud sync
Support
