obra · lockie · Jul 18, 2026
diff --git a/.eca-plugin/marketplace.json b/.eca-plugin/marketplace.json
@@ -0,0 +1,14 @@
+{
+  "plugins": [
+    {
+      "name": "superpowers",
+      "description": "Agentic development methodology: spec-driven brainstorming, structured planning, subagent-driven development, TDD, and systematic debugging",
+      "source": ".eca-plugin/superpowers",
+      "category": "Workflow",
+      "tags": ["methodology", "skill", "planning", "tdd", "debugging", "subagent", "workflow"],
+      "author": "obra",
+      "icon": "⚡",
+      "featured": true
+    }
+  ]
+}
diff --git a/.eca-plugin/superpowers/eca.json b/.eca-plugin/superpowers/eca.json
@@ -0,0 +1,5 @@
+{
+  "skills": [
+    {"path": "skills"}
+  ]
+}
diff --git a/.eca-plugin/superpowers/hooks/hooks.json b/.eca-plugin/superpowers/hooks/hooks.json
@@ -0,0 +1,22 @@
+{
+  "superpowers-bootstrap": {
+    "type": "chatStart",
+    "visible": false,
+    "actions": [
+      {
+        "type": "shell",
+        "file": "${plugin:root}/hooks/session-start"
+      }
+    ]
+  },
+  "superpowers-bootstrap-compact": {
+    "type": "postCompact",
+    "visible": false,
+    "actions": [
+      {
+        "type": "shell",
+        "file": "${plugin:root}/hooks/session-start"
+      }
+    ]
+  }
+}
diff --git a/.eca-plugin/superpowers/hooks/session-start b/.eca-plugin/superpowers/hooks/session-start
@@ -0,0 +1 @@
+../../../hooks/session-start
diff --git a/.eca-plugin/superpowers/skills b/.eca-plugin/superpowers/skills
@@ -0,0 +1 @@
+../../skills
diff --git a/.version-bump.json b/.version-bump.json
@@ -6,7 +6,8 @@
     { "path": ".codex-plugin/plugin.json", "field": "version" },
     { "path": ".kimi-plugin/plugin.json", "field": "version" },
     { "path": ".claude-plugin/marketplace.json", "field": "plugins.0.version" },
-    { "path": "gemini-extension.json", "field": "version" }
+    { "path": "gemini-extension.json", "field": "version" },
+    { "path": ".eca-plugin/marketplace.json", "field": "plugins.0.version" }
   ],
   "audit": {
     "exclude": [

diff --git a/README.md b/README.md
@@ -11,7 +11,7 @@ If this sounds like someone you know, definitely send them our way.
 
 ## Quickstart
 
-Give your agent Superpowers: [Claude Code](#claude-code), [Antigravity](#antigravity), [Codex App](#codex-app), [Codex CLI](#codex-cli), [Cursor](#cursor), [Factory Droid](#factory-droid), [Gemini CLI](#gemini-cli), [GitHub Copilot CLI](#github-copilot-cli), [Kimi Code](#kimi-code), [OpenCode](#opencode), [Pi](#pi).
+Give your agent Superpowers: [Claude Code](#claude-code), [Antigravity](#antigravity), [Codex App](#codex-app), [Codex CLI](#codex-cli), [Cursor](#cursor), [Factory Droid](#factory-droid), [Gemini CLI](#gemini-cli), [GitHub Copilot CLI](#github-copilot-cli), [Kimi Code](#kimi-code), [OpenCode](#opencode), [Pi](#pi), [ECA](#eca).
 
 ## How it works
 
@@ -199,6 +199,23 @@ pi -e /path/to/superpowers
 
 The Pi package loads the Superpowers skills and a small extension that injects the `using-superpowers` bootstrap at session startup and again after compaction. Pi has native skills, so no compatibility `Skill` tool is required. Subagent and task-list tools remain optional Pi companion packages.
 
+### ECA
+
+Add Superpowers as a plugin source in `~/.config/eca/config.json` (or `.eca/config.json` for project-local):
+
+```json
+{
+  "plugins": {
+    "superpowers-source": {
+      "source": "https://github.com/obra/superpowers.git"
+    },
+    "install": ["superpowers"]
+  }
+}
+```
+
+Restart ECA. Detailed docs: [docs/README.eca.md](docs/README.eca.md)
+
 ## The Basic Workflow
 
 1. **brainstorming** - Activates before writing code. Refines rough ideas through questions, explores alternatives, presents design in sections for validation. Saves design document.

diff --git a/docs/README.eca.md b/docs/README.eca.md
@@ -0,0 +1,105 @@
+# Superpowers for ECA (Editor Code Assistant)
+
+Complete guide for using Superpowers with [ECA](https://eca.dev).
+
+## Installation
+
+Add Superpowers as a plugin source in your ECA config:
+
+**Global config** (`~/.config/eca/config.json`):
+
+```json
+{
+  "plugins": {
+    "superpowers-source": {
+      "source": "https://github.com/obra/superpowers.git"
+    },
+    "install": ["superpowers"]
+  }
+}
+```
+
+**Project-local config** (`.eca/config.json`):
+
+```json
+{
+  "plugins": {
+    "superpowers-source": {
+      "source": "https://github.com/obra/superpowers.git"
+    },
+    "install": ["superpowers"]
+  }
+}
+```
+
+ECA's runtime plugin loader matches install entries against marketplace entries by exact name. The plugin marketplace entry is named `superpowers`, so the install list must say `"superpowers"` — not `"superpowers@source-name"`. The `@source` suffix is only parsed by the `/plugin-install` command, not by the loader that resolves plugins on session start.
+
+Restart ECA for the plugin to take effect.
+
+Verify by sending:
+
+> Tell me about your superpowers
+
+### Updating
+
+ECA re-resolves plugin sources on startup and periodically (approximately hourly). To force an update, restart ECA or clear the plugin cache at `~/.eca/cache/plugins/`.
+
+To pin a specific version, use a branch or tag in the source URL:
+
+```json
+{
+  "plugins": {
+    "superpowers-source": {
+      "source": "https://github.com/obra/superpowers.git#v5.1.0"
+    },
+    "install": ["superpowers"]
+  }
+}
+```
+
+## How It Works
+
+The plugin provides three things:
+
+1. **Skills** — All Superpowers skills are registered under the `superpowers:` namespace. ECA discovers them via the plugin's `skills/` directory (symlinked to the project's `skills/` root).
+2. **Bootstrap injection** — A `chatStart` hook runs the `session-start` script, which injects the `using-superpowers` skill content as additional context at the start of every chat.
+3. **Tool mapping** — The `using-superpowers` skill references `references/eca-tools.md` for ECA-specific tool name equivalents.
+
+### Skill Namespacing
+
+ECA plugins expose skills under a `<plugin-name>:<name>` namespace. Superpowers skills are accessed as:
+
+- `superpowers:brainstorming`
+- `superpowers:test-driven-development`
+- `superpowers:systematic-debugging`
+- `superpowers:using-superpowers`
+- etc.
+
+When the plugin name matches the skill name (as with `using-superpowers`), the qualified form `superpowers:using-superpowers` and the bare form `using-superpowers` both resolve.
+
+To manually invoke a skill:
+
+```
+Load the superpowers:brainstorming skill
+```
+
+## Troubleshooting
+
+### Plugin not loading
+
+1. Check that your `config.json` has the correct `source` URL.
+2. Verify the git repo is accessible: `git ls-remote https://github.com/obra/superpowers.git`
+3. Check ECA logs for plugin resolution errors.
+
+### Skills not found
+
+1. Use `/plugins` to verify `superpowers` appears in the plugin list.
+2. Confirm the `skills` symlink inside `.eca-plugin/superpowers/` resolves to the repo's `skills/` directory.
+
+### Bootstrap not appearing
+
+The `chatStart` hook runs `hooks/session-start`, which reads `skills/using-superpowers/SKILL.md` and injects it as `additionalContext`. If the bootstrap is missing:
+
+1. Check that the `session-start` symlink resolves to the repo-root `hooks/session-start` script.
+2. Confirm the hook is registered in `.eca-plugin/superpowers/hooks/hooks.json` with `"type": "chatStart"`.
+3. Start a new session — hooks fire on chat start, not mid-session.
diff --git a/docs/porting-to-a-new-harness.md b/docs/porting-to-a-new-harness.md
@@ -792,6 +792,7 @@ Use this as the live index; when in doubt, read the files, not this table.
 | Kimi Code | `.kimi-plugin/plugin.json` | manifest `sessionStart.skill` loads `using-superpowers` | inline `skillInstructions` in manifest | `tests/kimi/` | marketplace or `/plugins install` GitHub URL |
 | OpenCode | `.opencode/plugins/superpowers.js` (declared via root `package.json` `main`) | in-process: `config` hook registers skills dir; `experimental.chat.messages.transform` injects user message | inline in `superpowers.js` | `tests/opencode/` | `opencode.json` plugin git URL |
 | pi | `.pi/extensions/superpowers.ts` | in-process: `resources_discover` registers skills; `context` event injects user message; lifecycle-flag + compaction-aware | `piToolMapping()` inline **and** `references/pi-tools.md` | `tests/pi/` | repo-root `package.json` fields |
+| ECA | `.eca-plugin/marketplace.json` + `.eca-plugin/superpowers/eca.json` | shell hook → `hooks/session-start` (`additionalContext`); `chatStart` + `postCompact` hooks | `references/eca-tools.md` | `tests/hooks/`, `tests/eca/` | plugin source (git URL or local path) |
 
 ## Appendix B — Gotchas that have bitten porters
 

diff --git a/hooks/session-start b/hooks/session-start
@@ -42,7 +42,8 @@ elif [ -n "${CLAUDE_PLUGIN_ROOT:-}" ] && [ -z "${COPILOT_CLI:-}" ]; then
   # Claude Code sets CLAUDE_PLUGIN_ROOT without COPILOT_CLI
   printf '{\n  "hookSpecificOutput": {\n    "hookEventName": "SessionStart",\n    "additionalContext": "%s"\n  }\n}\n' "$session_context" | cat
 else
-  # Copilot CLI (sets COPILOT_CLI=1) or unknown platform — SDK standard format
+  # Copilot CLI (sets COPILOT_CLI=1), ECA (no harness env vars), or unknown
+  # platform — SDK standard format
   printf '{\n  "additionalContext": "%s"\n}\n' "$session_context" | cat
 fi
 

diff --git a/scripts/sync-to-codex-plugin.sh b/scripts/sync-to-codex-plugin.sh
@@ -48,6 +48,7 @@ EXCLUDES=(
   "/.claude-plugin/"
   "/.codex/"
   "/.cursor-plugin/"
+  "/.eca-plugin/"
   "/.git/"
   "/.gitattributes"
   "/.github/"

diff --git a/skills/using-superpowers/SKILL.md b/skills/using-superpowers/SKILL.md
@@ -56,6 +56,7 @@ If your harness appears here, read its reference file for special instructions:
 - Codex: `references/codex-tools.md`
 - Pi: `references/pi-tools.md`
 - Antigravity: `references/antigravity-tools.md`
+- ECA: `references/eca-tools.md`
 
 ## User Instructions
 

diff --git a/skills/using-superpowers/references/eca-tools.md b/skills/using-superpowers/references/eca-tools.md
@@ -0,0 +1,44 @@
+# ECA Tool Mapping
+
+Skills speak in actions ("dispatch a subagent", "create a todo", "read a file"). On ECA (Editor Code Assistant) these resolve to the tools below.
+
+| Action skills request | ECA equivalent |
+|----------------------|----------------|
+| Read a file | `eca__read_file` |
+| Create / overwrite a file | `eca__write_file` |
+| Edit a file (targeted replace) | `eca__edit_file` |
+| Move / rename a file | `eca__move_file` |
+| Run a shell command | `eca__shell_command` |
+| Search file contents | `eca__grep` |
+| List directory tree | `eca__directory_tree` |
+| Task tracking ("create a todo", "mark complete") | `eca__task` |
+| Invoke a skill | `eca__skill` |
+| Check editor diagnostics | `eca__editor_diagnostics` |
+| Git operations | `eca__git` |
+| Fetch a URL / web search | `eca__shell_command` (use `curl`/`wget`) |
+
+## Subagent support
+
+ECA supports subagents via the `eca__spawn_agent` tool. Available agent types:
+
+- `general` — General-purpose agent for complex multi-step tasks and research.
+- `explorer` — Codebase search specialist for finding and reading file contents.
+
+When a skill says to dispatch a named agent type, use `eca__spawn_agent` with the appropriate agent and a detailed task prompt:
+
+| Skill instruction | ECA equivalent |
+|-------------------|----------------|
+| `Task tool (superpowers:implementer)` | `eca__spawn_agent(agent: "general", task: "<filled implementer-prompt.md>")` |
+| `Task tool (superpowers:spec-reviewer)` | `eca__spawn_agent(agent: "general", task: "<filled spec-reviewer-prompt.md>")` |
+| `Task tool (superpowers:code-reviewer)` | `eca__spawn_agent(agent: "general", task: "<filled code-reviewer.md>")` |
+| `Task tool (superpowers:code-quality-reviewer)` | `eca__spawn_agent(agent: "general", task: "<filled code-quality-reviewer-prompt.md>")` |
+| `Task tool (general-purpose)` with inline prompt | `eca__spawn_agent(agent: "general", task: "<inline prompt>")` |
+| `Task tool (explorer)` | `eca__spawn_agent(agent: "explorer", task: "<exploration task>")` |
+
+### Prompt filling
+
+Skills provide prompt templates with placeholders like `{WHAT_WAS_IMPLEMENTED}` or `[FULL TEXT of task]`. Fill all placeholders and pass the complete prompt as the `task` argument to `eca__spawn_agent`.
+
+### Parallel dispatch
+
+ECA supports parallel subagent dispatch. When a skill asks you to dispatch multiple independent subagent tasks in parallel, issue the `eca__spawn_agent` calls together. Keep dependent tasks sequential.
diff --git a/tests/eca/run-tests.sh b/tests/eca/run-tests.sh
@@ -0,0 +1,7 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+
+echo "Running ECA plugin structure tests..."
+bash "$SCRIPT_DIR/test-plugin-structure.sh"