Tool integration · Claude Code

How Foundry surfaces inside Anthropic's Claude Code CLI.

Foundry currently supports four tools, all with the same full-skill install: Claude Code (.claude/skills/), Cursor and Codex (shared .agents/skills/), and OpenCode (.opencode/skills/). Other IDEs are not currently supported.

What the installer writes

When you select Claude Code during npx @engineering11/e11-foundry install, the installer writes complete skill directories into:

.claude/skills/
├── e11-master/
│   ├── SKILL.md
│   └── customize.toml
├── e11-agent-dev/
│   ├── SKILL.md
│   └── customize.toml
├── e11-code-review/
│   ├── SKILL.md
│   ├── customize.toml
│   └── steps/
├── ...              # one directory per installed skill — agents, workflows, tasks

Each skill is self-contained: SKILL.md with clean frontmatter (name, description), its customize.toml surface, and any step files, templates, and references it loads at run time. Claude Code reads the directory natively — nothing Foundry-specific sits between the tool and the skill.

Legacy installs may have files under .claude/commands/ — the installer cleans those up on update.

Invoking a skill

Claude Code surfaces each directory as an invokable skill. Common patterns:

> e11-master                                # the entry point — catalog menu + routing
> use the e11-agent-dev skill               # become the Dev agent
> skill:e11-code-review staged changes      # run a workflow directly with an argument
> skill:e11-knowledge sdk:auth              # one-shot knowledge query

If you don't know which skill you need, start with e11-master — it loads .foundry/_config/e11-help.csv (the catalog of everything installed) and routes. e11-help ([BH]) answers "what should I do next?" from anywhere.

Picking a command

Agent menus use 2–3 letter command codes (CB, PR, CA, DS, …). After an agent greets you, type the code, a number, or describe what you want — fuzzy matching is built into every menu:

> DS                                        # short
> dev story                                 # fuzzy match
> start implementation of story 2-3         # natural language; Dev picks [DS]

Full code catalog: first-run.md or .foundry/_config/e11-help.csv.

Skill scope (project vs user)

The installer writes to .claude/skills/ in the current project by default. That's per-project — skills you install in repo A aren't visible in repo B. For a global install, re-run the installer with --directory ~; the skill format is identical.

Ancestor-directory conflict check

If Foundry skills are already installed in a parent directory (e.g. you installed in ~ and now install in ~/projects/foo), the installer detects the conflict and refuses to double-write — tools that inherit skills from parent directories would see two copies. Remove the ancestor install or skip the child install.

Headless

Claude Code is also a supported runtime for Foundry's headless CLI:

e11 agent --list                              # what's installed here
e11 agent dev "run e11-dev-auto for story 3-2" --runtime claude
e11 pipeline                                  # run .foundry/pipeline.yaml step by step

e11 agent assembles the skill's activation prompt and your task, then drives the claude CLI non-interactively. e11 pipeline chains agents through the artifacts they write to disk — see Unattended runs.

Tips

• Skill descriptions matter. The description: frontmatter is what Claude Code uses to match your request to a skill. If invocations aren't routing correctly, check the description of the skill you're trying to reach.
• Pair with /cost to track usage. Foundry workflows can be long (especially Phase 4). Check between phases.
• Use a fresh context for [CR] Code Review. Open a new session with claude rather than continuing the implementation session. The reviewer needs cold eyes.
• @engineering11/alloy reads happen in the current cwd. Invoke Claude Code from the project root where alloy is installed; otherwise skill:e11-knowledge halts with an install instruction.
• Customize from .foundry/custom/, not the skill dirs. Files under .claude/skills/ are overwritten on update; your overrides aren't. See Customization.

What this page does not cover

• Authentication or billing for Claude Code itself — see Anthropic's docs.
• Customising the Claude Code context window or system prompt.
• Building your own non-Foundry skills.

Source

Platform config: tools/cli/installers/lib/ide/platform-codes.yaml (see the claude-code: entry) · headless CLI: tools/cli/commands/agent.ts, tools/cli/commands/pipeline.ts

See also: Installation · First run · Codex · OpenCode.