diff --git a/openspec/changes/add-opencode-slash-commands/proposal.md b/openspec/changes/add-opencode-slash-commands/proposal.md
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+# Add OpenCode Slash Command Support
+
+## Summary
+- Extend OpenSpec's slash command scaffolding to support OpenCode's `.opencode/command/` markdown commands alongside Claude and Cursor.
+- Generate and refresh three workflow-aligned commands (`openspec-proposal`, `openspec-apply`, `openspec-archive`) using the shared templates already used by other agents.
+- Ensure OpenCode appears in the CLI tool selection flow so teams can opt into slash command automation during `init` and keep them updated via `update`.
+
+## Motivation
+Teams adopting OpenSpec increasingly rely on OpenCode's slash command system to standardize how collaborators invoke AI helpers. We already provide purpose-built commands for Claude and Cursor to guide proposal, implementation, and archiving flows. Without equivalent commands in OpenCode, mixed-tool teams must recreate these instructions manually, leading to drift and inconsistent workflows. Adding first-class OpenCode support keeps multi-agent teams aligned and reduces setup friction for users migrating between tools.
+
+## Proposal
+1. **Tool selection**
+   - Add OpenCode as an available configurator in the interactive `openspec init` flow (and any non-interactive selection plumbing).
+   - Describe the option as creating `.opencode/command/*.md` slash commands so users understand the outcome.
+2. **Slash command generation**
+   - Reuse the shared slash command template bodies and produce three files under `.opencode/command/`: `openspec-proposal.md`, `openspec-apply.md`, and `openspec-archive.md`.
+   - Wrap command content in OpenSpec markers placed after any YAML frontmatter so future updates remain idempotent.
+   - Populate frontmatter with at minimum a `description` summarizing the workflow stage; allow optional OpenCode-specific keys (`agent`, `model`) to remain user-editable outside the markers.
+3. **Slash command updates**
+   - During `openspec update`, detect existing `.opencode/command/openspec-*.md` files and refresh only the managed sections using the same templates.
+   - Skip creation if the files are missing, mirroring current behavior for other tools.
+4. **User feedback & documentation**
+   - Reflect OpenCode updates in CLI logging alongside Claude and Cursor so users see which commands changed.
+   - Update any user-facing success messaging or docs snippets that enumerate supported slash-command tools.
+
+## Open Questions
+- Should we scaffold default `agent` and `model` values in the frontmatter, or leave them blank so teams can decide which OpenCode agent executes each command?
+- Do we need a migration strategy if existing OpenCode commands already exist with different filenames or markers?
+
+## Out of Scope
+- Adding additional OpenSpec commands beyond the core proposal/apply/archive trio.
+- Building a standalone command to regenerate slash commands outside of `init`/`update`.
+
+## Dependencies
+- Shares the slash command template system introduced in `add-slash-command-support`; confirm the templates can emit OpenCode-specific wrappers without duplication.
diff --git a/openspec/changes/add-opencode-slash-commands/specs/cli-init/spec.md b/openspec/changes/add-opencode-slash-commands/specs/cli-init/spec.md
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+## MODIFIED Requirements
+### Requirement: AI Tool Configuration
+
+The command SHALL configure AI coding assistants with OpenSpec instructions based on user selection.
+
+#### Scenario: Prompting for AI tool selection
+
+- **WHEN** run interactively
+- **THEN** prompt the user with "Which AI tools do you use?" using a multi-select menu
+- **AND** list every available tool with a checkbox:
+  - Claude Code (creates or refreshes CLAUDE.md and slash commands)
+  - Cursor (creates or refreshes `.cursor/commands/*` slash commands)
+  - OpenCode (creates or refreshes `.opencode/command/openspec-*.md` slash commands)
+  - AGENTS.md standard (creates or refreshes AGENTS.md with OpenSpec markers)
+- **AND** show "(already configured)" beside tools whose managed files exist so users understand selections will refresh content
+- **AND** treat disabled tools as "coming soon" and keep them unselectable
+- **AND** allow confirming with Enter after selecting one or more tools
+
+### Requirement: AI Tool Configuration Details
+
+The command SHALL properly configure selected AI tools with OpenSpec-specific instructions using a marker system.
+
+#### Scenario: Configuring OpenCode
+
+- **WHEN** OpenCode is selected
+- **THEN** create or update `.opencode/command/openspec-proposal.md`, `.opencode/command/openspec-apply.md`, and `.opencode/command/openspec-archive.md`
+- **AND** ensure the `command/` directory exists before writing files
+- **AND** place OpenSpec markers around the shared command body while leaving any YAML frontmatter intact for user customization
+- **AND** align visible slash names, filenames, and any frontmatter identifiers (e.g., `/openspec-proposal`, `openspec-proposal.md`)
+
+### Requirement: Interactive Mode
+
+The command SHALL provide an interactive menu for AI tool selection with clear navigation instructions.
+
+#### Scenario: Displaying interactive menu
+
+- **WHEN** run
+- **THEN** prompt the user with: "Which AI tools do you use?"
+- **AND** show a checkbox-based multi-select menu with available tools (Claude Code, Cursor, OpenCode, AGENTS.md standard)
+- **AND** show disabled options as "coming soon" (not selectable)
+- **AND** display inline help indicating Space toggles selections and Enter confirms
+
+## MODIFIED Requirements
+### Requirement: Slash Command Configuration
+The init command SHALL generate slash command files for supported editors using shared templates.
+
+#### Scenario: Generating slash commands for Claude Code
+- **WHEN** the user selects Claude Code during initialization
+- **THEN** create `.claude/commands/openspec/proposal.md`, `.claude/commands/openspec/apply.md`, and `.claude/commands/openspec/archive.md`
+- **AND** populate each file from shared templates so command text matches other tools
+- **AND** each template includes instructions for the relevant OpenSpec workflow stage
+
+#### Scenario: Generating slash commands for Cursor
+- **WHEN** the user selects Cursor during initialization
+- **THEN** create `.cursor/commands/openspec-proposal.md`, `.cursor/commands/openspec-apply.md`, and `.cursor/commands/openspec-archive.md`
+- **AND** populate each file from shared templates so command text matches other tools
+- **AND** each template includes instructions for the relevant OpenSpec workflow stage
+
+#### Scenario: Generating slash commands for OpenCode
+- **WHEN** the user selects OpenCode during initialization
+- **THEN** create `.opencode/command/openspec-proposal.md`, `.opencode/command/openspec-apply.md`, and `.opencode/command/openspec-archive.md`
+- **AND** populate each file from shared templates so command text matches other tools
+- **AND** each template includes instructions for the relevant OpenSpec workflow stage
+- **AND** place OpenSpec markers after any YAML frontmatter so updates remain idempotent
diff --git a/openspec/changes/add-opencode-slash-commands/specs/cli-update/spec.md b/openspec/changes/add-opencode-slash-commands/specs/cli-update/spec.md
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+## MODIFIED Requirements
+### Requirement: Slash Command Updates
+The update command SHALL refresh existing slash command files for configured tools without creating new ones.
+
+#### Scenario: Updating slash commands for Claude Code
+- **WHEN** `.claude/commands/openspec/` contains `proposal.md`, `apply.md`, and `archive.md`
+- **THEN** refresh each file using shared templates
+- **AND** ensure templates include instructions for the relevant workflow stage
+
+#### Scenario: Updating slash commands for Cursor
+- **WHEN** `.cursor/commands/` contains `openspec-proposal.md`, `openspec-apply.md`, and `openspec-archive.md`
+- **THEN** refresh each file using shared templates
+- **AND** ensure templates include instructions for the relevant workflow stage
+
+#### Scenario: Updating slash commands for OpenCode
+- **WHEN** `.opencode/command/` contains `openspec-proposal.md`, `openspec-apply.md`, and `openspec-archive.md`
+- **THEN** refresh each file using shared templates
+- **AND** keep OpenSpec markers wrapped around the command body so user frontmatter stays intact
+
+#### Scenario: Missing slash command file
+- **WHEN** a tool lacks a slash command file
+- **THEN** do not create a new file during update
diff --git a/openspec/changes/add-opencode-slash-commands/tasks.md b/openspec/changes/add-opencode-slash-commands/tasks.md
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+# Tasks
+
+- [ ] 1. Update the CLI tool registry and interactive prompts to list OpenCode as a configurable assistant.
+  - [ ] 1.1 Ensure non-interactive selections (flags/env) accept OpenCode identifiers.
+- [ ] 2. Extend the slash command configurator to emit OpenCode targets using the shared templates.
+  - [ ] 2.1 Generate `.opencode/command/openspec-{proposal,apply,archive}.md` with proper marker placement.
+  - [ ] 2.2 Populate descriptive frontmatter while leaving user-editable metadata outside the managed block.
+- [ ] 3. Teach `openspec update` to detect and refresh existing OpenCode command files without creating new ones.
+  - [ ] 3.1 Log per-file update results alongside other tools.
+- [ ] 4. Add automated coverage (or golden fixtures) for OpenCode generation and update flows.
+  - [ ] 4.1 Include mixed-tool scenarios where only some commands exist to confirm update skips missing files.
+- [ ] 5. Refresh user-facing docs or success messaging that enumerates slash-command capable tools.