WIP

Nathan Sobo created

Change summary

.claude/commands/create_plan.md                                           | 141 
.claude/commands/founder_mode.md                                          |  15 
.claude/commands/implement_plan.md                                        |   2 
.claude/settings.local.json                                               |  28 
Cargo.lock                                                                |   4 
Cargo.toml                                                                |   2 
crates/acp_thread/src/acp_thread.rs                                       |   5 
crates/acp_thread/src/connection.rs                                       |  11 
crates/agent2/src/agent.rs                                                |  13 
crates/agent2/src/thread.rs                                               |   1 
crates/agent_servers/src/acp.rs                                           |  18 
crates/agent_servers/src/claude.rs                                        |  14 
crates/agent_ui/src/acp/completion_provider.rs                            |   1 
crates/agent_ui/src/acp/message_editor.rs                                 |  13 
crates/agent_ui/src/acp/thread_view.rs                                    |   8 
script/spec_metadata.sh                                                   |  69 
thoughts/shared/research/2025-08-28_15-34-28_custom-slash-commands-acp.md | 337 
17 files changed, 467 insertions(+), 215 deletions(-)

Detailed changes

.claude/commands/create_plan.md 🔗

@@ -12,6 +12,7 @@ When this command is invoked:
    - Begin the research process
 
 2. **If no parameters provided**, respond with:
+
 ```
 I'll help you create a detailed implementation plan. Let me start by understanding what we're building.
 
@@ -43,11 +44,8 @@ Then wait for the user's input.
 
 2. **Spawn initial research tasks to gather context**:
    Before asking the user any questions, use specialized agents to research in parallel:
-
    - Use the **codebase-locator** agent to find all files related to the ticket/task
    - Use the **codebase-analyzer** agent to understand how the current implementation works
-   - If relevant, use the **thoughts-locator** agent to find any existing thoughts documents about this feature
-   - If a Linear ticket is mentioned, use the **linear-ticket-reader** agent to get full details
 
    These agents will:
    - Find relevant source files, configs, and tests
@@ -67,6 +65,7 @@ Then wait for the user's input.
    - Determine true scope based on codebase reality
 
 5. **Present informed understanding and focused questions**:
+
    ```
    Based on the ticket and my research of the codebase, I understand we need to [accurate summary].
 
@@ -118,9 +117,10 @@ After getting initial clarifications:
    - Return specific file:line references
    - Find tests and examples
 
-3. **Wait for ALL sub-tasks to complete** before proceeding
+4. **Wait for ALL sub-tasks to complete** before proceeding
+
+5. **Present findings and design options**:
 
-4. **Present findings and design options**:
    ```
    Based on my research, here's what I found:
 
@@ -144,6 +144,7 @@ After getting initial clarifications:
 Once aligned on approach:
 
 1. **Create initial plan outline**:
+
    ```
    Here's my proposed plan structure:
 
@@ -167,7 +168,7 @@ After structure approval:
 1. **Write the plan** to `thoughts/shared/plans/{descriptive_name}.md`
 2. **Use this template structure**:
 
-```markdown
+````markdown
 # [Feature/Task Name] Implementation Plan
 
 ## Overview
@@ -183,6 +184,7 @@ After structure approval:
 [A Specification of the desired end state after this plan is complete, and how to verify it]
 
 ### Key Discoveries:
+
 - [Important finding with file:line reference]
 - [Pattern to follow]
 - [Constraint to work within]
@@ -198,21 +200,25 @@ After structure approval:
 ## Phase 1: [Descriptive Name]
 
 ### Overview
+
 [What this phase accomplishes]
 
 ### Changes Required:
 
 #### 1. [Component/File Group]
+
 **File**: `path/to/file.ext`
 **Changes**: [Summary of changes]
 
 ```[language]
 // Specific code to add/modify
 ```
+````
 
 ### Success Criteria:
 
 #### Automated Verification:
+
 - [ ] Migration applies cleanly: `make migrate`
 - [ ] Unit tests pass: `make test-component`
 - [ ] Type checking passes: `npm run typecheck`
@@ -220,6 +226,7 @@ After structure approval:
 - [ ] Integration tests pass: `make test-integration`
 
 #### Manual Verification:
+
 - [ ] Feature works as expected when tested via UI
 - [ ] Performance is acceptable under load
 - [ ] Edge case handling verified manually
@@ -236,13 +243,16 @@ After structure approval:
 ## Testing Strategy
 
 ### Unit Tests:
+
 - [What to test]
 - [Key edge cases]
 
 ### Integration Tests:
+
 - [End-to-end scenarios]
 
 ### Manual Testing Steps:
+
 1. [Specific step to verify feature]
 2. [Another verification step]
 3. [Edge case to test manually]
@@ -260,6 +270,7 @@ After structure approval:
 - Original ticket: `thoughts/allison/tickets/eng_XXXX.md`
 - Related research: `thoughts/shared/research/[relevant].md`
 - Similar implementation: `[file:line]`
+
 ```
 
 ### Step 5: Sync and Review
@@ -269,80 +280,83 @@ After structure approval:
    - This ensures the plan is properly indexed and available
 
 2. **Present the draft plan location**:
-   ```
-   I've created the initial implementation plan at:
-   `thoughts/shared/plans/[filename].md`
-
-   Please review it and let me know:
-   - Are the phases properly scoped?
-   - Are the success criteria specific enough?
-   - Any technical details that need adjustment?
-   - Missing edge cases or considerations?
-   ```
+```
+
+I've created the initial implementation plan at:
+`thoughts/shared/plans/[filename].md`
+
+Please review it and let me know:
+
+- Are the phases properly scoped?
+- Are the success criteria specific enough?
+- Any technical details that need adjustment?
+- Missing edge cases or considerations?
+
+````
 
 3. **Iterate based on feedback** - be ready to:
-   - Add missing phases
-   - Adjust technical approach
-   - Clarify success criteria (both automated and manual)
-   - Add/remove scope items
-   - After making changes, run `humanlayer thoughts sync` again
+- Add missing phases
+- Adjust technical approach
+- Clarify success criteria (both automated and manual)
+- Add/remove scope items
+- After making changes, run `humanlayer thoughts sync` again
 
 4. **Continue refining** until the user is satisfied
 
 ## Important Guidelines
 
 1. **Be Skeptical**:
-   - Question vague requirements
-   - Identify potential issues early
-   - Ask "why" and "what about"
-   - Don't assume - verify with code
+- Question vague requirements
+- Identify potential issues early
+- Ask "why" and "what about"
+- Don't assume - verify with code
 
 2. **Be Interactive**:
-   - Don't write the full plan in one shot
-   - Get buy-in at each major step
-   - Allow course corrections
-   - Work collaboratively
+- Don't write the full plan in one shot
+- Get buy-in at each major step
+- Allow course corrections
+- Work collaboratively
 
 3. **Be Thorough**:
-   - Read all context files COMPLETELY before planning
-   - Research actual code patterns using parallel sub-tasks
-   - Include specific file paths and line numbers
-   - Write measurable success criteria with clear automated vs manual distinction
-   - automated steps should use `make` whenever possible - for example `make -C humanlayer-wui check` instead of `cd humanalyer-wui && bun run fmt`
+- Read all context files COMPLETELY before planning
+- Research actual code patterns using parallel sub-tasks
+- Include specific file paths and line numbers
+- Write measurable success criteria with clear automated vs manual distinction
+- automated steps should use `make` whenever possible - for example `make -C humanlayer-wui check` instead of `cd humanalyer-wui && bun run fmt`
 
 4. **Be Practical**:
-   - Focus on incremental, testable changes
-   - Consider migration and rollback
-   - Think about edge cases
-   - Include "what we're NOT doing"
+- Focus on incremental, testable changes
+- Consider migration and rollback
+- Think about edge cases
+- Include "what we're NOT doing"
 
 5. **Track Progress**:
-   - Use TodoWrite to track planning tasks
-   - Update todos as you complete research
-   - Mark planning tasks complete when done
+- Use TodoWrite to track planning tasks
+- Update todos as you complete research
+- Mark planning tasks complete when done
 
 6. **No Open Questions in Final Plan**:
-   - If you encounter open questions during planning, STOP
-   - Research or ask for clarification immediately
-   - Do NOT write the plan with unresolved questions
-   - The implementation plan must be complete and actionable
-   - Every decision must be made before finalizing the plan
+- If you encounter open questions during planning, STOP
+- Research or ask for clarification immediately
+- Do NOT write the plan with unresolved questions
+- The implementation plan must be complete and actionable
+- Every decision must be made before finalizing the plan
 
 ## Success Criteria Guidelines
 
 **Always separate success criteria into two categories:**
 
 1. **Automated Verification** (can be run by execution agents):
-   - Commands that can be run: `make test`, `npm run lint`, etc.
-   - Specific files that should exist
-   - Code compilation/type checking
-   - Automated test suites
+- Commands that can be run: `make test`, `npm run lint`, etc.
+- Specific files that should exist
+- Code compilation/type checking
+- Automated test suites
 
 2. **Manual Verification** (requires human testing):
-   - UI/UX functionality
-   - Performance under real conditions
-   - Edge cases that are hard to automate
-   - User acceptance criteria
+- UI/UX functionality
+- Performance under real conditions
+- Edge cases that are hard to automate
+- User acceptance criteria
 
 **Format example:**
 ```markdown
@@ -359,11 +373,12 @@ After structure approval:
 - [ ] Performance is acceptable with 1000+ items
 - [ ] Error messages are user-friendly
 - [ ] Feature works correctly on mobile devices
-```
+````
 
 ## Common Patterns
 
 ### For Database Changes:
+
 - Start with schema/migration
 - Add store methods
 - Update business logic
@@ -371,6 +386,7 @@ After structure approval:
 - Update clients
 
 ### For New Features:
+
 - Research existing patterns first
 - Start with data model
 - Build backend logic
@@ -378,6 +394,7 @@ After structure approval:
 - Implement UI last
 
 ### For Refactoring:
+
 - Document current behavior
 - Plan incremental changes
 - Maintain backwards compatibility
@@ -394,20 +411,16 @@ When spawning research sub-tasks:
    - Which directories to focus on
    - What information to extract
    - Expected output format
-4. **Be EXTREMELY specific about directories**:
-   - If the ticket mentions "WUI", specify `humanlayer-wui/` directory
-   - If it mentions "daemon", specify `hld/` directory
-   - Never use generic terms like "UI" when you mean "WUI"
-   - Include the full path context in your prompts
-5. **Specify read-only tools** to use
-6. **Request specific file:line references** in responses
-7. **Wait for all tasks to complete** before synthesizing
-8. **Verify sub-task results**:
+4. **Specify read-only tools** to use
+5. **Request specific file:line references** in responses
+6. **Wait for all tasks to complete** before synthesizing
+7. **Verify sub-task results**:
    - If a sub-task returns unexpected results, spawn follow-up tasks
    - Cross-check findings against the actual codebase
    - Don't accept results that seem incorrect
 
 Example of spawning multiple tasks:
+
 ```python
 # Spawn these tasks concurrently:
 tasks = [

.claude/commands/founder_mode.md 🔗

@@ -1,15 +0,0 @@
-you're working on an experimental feature that didn't get the proper ticketing and pr stuff set up.
-
-assuming you just made a commit, here are the next steps:
-
-
-1. get the sha of the commit you just made (if you didn't make one, read `.claude/commands/commit.md` and make one)
-
-2. read `.claude/commands/linear.md` - think deeply about what you just implemented, then create a linear ticket about what you just did, and put it in 'in dev' state - it should have ### headers for "problem to solve" and "proposed solution"
-3. fetch the ticket to get the recommended git branch name
-4. git checkout main
-5. git checkout -b 'BRANCHNAME'
-6. git cherry-pick 'COMMITHASH'
-7. git push -u origin 'BRANCHNAME'
-8. gh pr create --fill
-9. read '.claude/commands/describe_pr.md' and follow the instructions

.claude/commands/implement_plan.md 🔗

@@ -39,7 +39,7 @@ If you encounter a mismatch:
 ## Verification Approach
 
 After implementing a phase:
-- Run the success criteria checks (usually `make check test` covers everything)
+- Run the success criteria checks (usually `cargo test -p [crate_name]` covers everything)
 - Fix any issues before proceeding
 - Update your progress in both the plan and your todos
 - Check off completed items in the plan file itself using Edit

.claude/settings.local.json 🔗

@@ -1,11 +1,31 @@
 {
   "permissions": {
+    "allow": [
+      "Read(/Users/mikaylamaki/projects/zed-work/zed-monorepo-real/**)",
+      "Read(/Users/nathan/src/agent-client-protocol/rust/**)",
+      "Read(/Users/nathan/src/agent-client-protocol/rust/**)",
+      "Read(/Users/nathan/src/agent-client-protocol/rust/**)",
+      "Read(/Users/nathan/src/agent-client-protocol/rust/**)",
+      "Bash(git add:*)",
+      "Read(/Users/nathan/src/agent-client-protocol/rust/**)",
+      "Bash(./script/spec_metadata.sh:*)",
+      "Bash(npm run generate:*)",
+      "Bash(npm run typecheck:*)",
+      "Bash(npm run:*)",
+      "Bash(npm install)",
+      "Bash(grep:*)",
+      "Bash(find:*)",
+      "Bash(node:*)",
+      "Bash(cargo check:*)",
+      "Bash(cargo test)",
+      "Bash(npx tsc:*)"
+    ],
     "additionalDirectories": [
       "/Users/mikaylamaki/projects/zed-work/zed-monorepo-real/claude-code-acp/",
-      "/Users/mikaylamaki/projects/zed-work/zed-monorepo-real/agentic-coding-protocol/"
-    ],
-    "allow": [
-      "Read(/Users/mikaylamaki/projects/zed-work/zed-monorepo-real/**)"
+      "/Users/mikaylamaki/projects/zed-work/zed-monorepo-real/agentic-coding-protocol/",
+      "/Users/nathan/src/agent",
+      "/Users/nathan/src/agent-client-protocol/",
+      "/Users/nathan/src/claude-code-acp"
     ]
   }
 }

Cargo.lock 🔗

@@ -191,9 +191,7 @@ dependencies = [
 
 [[package]]
 name = "agent-client-protocol"
-version = "0.0.31"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "289eb34ee17213dadcca47eedadd386a5e7678094095414e475965d1bcca2860"
+version = "0.2.0-alpha.0"
 dependencies = [
  "anyhow",
  "async-broadcast",

Cargo.toml 🔗

@@ -426,7 +426,7 @@ zlog_settings = { path = "crates/zlog_settings" }
 # External crates
 #
 
-agent-client-protocol = "0.0.31"
+agent-client-protocol = { path = "../agent-client-protocol" }
 aho-corasick = "1.1"
 alacritty_terminal = { git = "https://github.com/zed-industries/alacritty.git", branch = "add-hush-login-flag" }
 any_vec = "0.14"

crates/acp_thread/src/acp_thread.rs 🔗

@@ -868,6 +868,11 @@ impl AcpThread {
         &self.connection
     }
 
+    /// Returns true if the agent supports custom slash commands.
+    pub fn supports_custom_commands(&self) -> bool {
+        self.prompt_capabilities.supports_custom_commands
+    }
+
     pub fn action_log(&self) -> &Entity<ActionLog> {
         &self.action_log
     }

crates/acp_thread/src/connection.rs 🔗

@@ -76,6 +76,9 @@ pub trait AgentConnection {
         None
     }
 
+    fn list_commands(&self, session_id: &acp::SessionId, cx: &mut App) -> Task<Result<acp::ListCommandsResponse>>;
+    fn run_command(&self, request: acp::RunCommandRequest, cx: &mut App) -> Task<Result<()>>;
+
     fn into_any(self: Rc<Self>) -> Rc<dyn Any>;
 }
 
@@ -440,6 +443,14 @@ mod test_support {
             Some(Rc::new(StubAgentSessionEditor))
         }
 
+        fn list_commands(&self, _session_id: &acp::SessionId, _cx: &mut App) -> Task<Result<acp::ListCommandsResponse>> {
+            Task::ready(Ok(acp::ListCommandsResponse { commands: vec![] }))
+        }
+
+        fn run_command(&self, _request: acp::RunCommandRequest, _cx: &mut App) -> Task<Result<()>> {
+            Task::ready(Ok(()))
+        }
+
         fn into_any(self: Rc<Self>) -> Rc<dyn Any> {
             self
         }

crates/agent2/src/agent.rs 🔗

@@ -1027,6 +1027,19 @@ impl acp_thread::AgentConnection for NativeAgentConnection {
         Some(Rc::new(self.clone()) as Rc<dyn acp_thread::AgentTelemetry>)
     }
 
+    fn list_commands(&self, session_id: &acp::SessionId, _cx: &mut App) -> Task<Result<acp::ListCommandsResponse>> {
+        // Native agent doesn't support custom commands yet
+        let _session_id = session_id.clone();
+        Task::ready(Ok(acp::ListCommandsResponse {
+            commands: vec![],
+        }))
+    }
+
+    fn run_command(&self, _request: acp::RunCommandRequest, _cx: &mut App) -> Task<Result<()>> {
+        // Native agent doesn't support custom commands yet
+        Task::ready(Err(anyhow!("Custom commands not supported")))
+    }
+
     fn into_any(self: Rc<Self>) -> Rc<dyn Any> {
         self
     }

crates/agent_servers/src/acp.rs 🔗

@@ -136,6 +136,7 @@ impl AcpConnection {
                         read_text_file: true,
                         write_text_file: true,
                     },
+                    terminal: true,
                 },
             })
             .await?;
@@ -328,6 +329,23 @@ impl AgentConnection for AcpConnection {
             .detach();
     }
 
+    fn list_commands(&self, session_id: &acp::SessionId, cx: &mut App) -> Task<Result<acp::ListCommandsResponse>> {
+        let conn = self.connection.clone();
+        let session_id = session_id.clone();
+        cx.foreground_executor().spawn(async move {
+            conn.list_commands(acp::ListCommandsRequest { session_id }).await
+                .map_err(Into::into)
+        })
+    }
+
+    fn run_command(&self, request: acp::RunCommandRequest, cx: &mut App) -> Task<Result<()>> {
+        let conn = self.connection.clone();
+        cx.foreground_executor().spawn(async move {
+            conn.run_command(request).await
+                .map_err(Into::into)
+        })
+    }
+
     fn into_any(self: Rc<Self>) -> Rc<dyn Any> {
         self
     }

crates/agent_servers/src/claude.rs 🔗

@@ -244,6 +244,7 @@ impl AgentConnection for ClaudeAgentConnection {
                         image: true,
                         audio: false,
                         embedded_context: true,
+                        supports_custom_commands: false,
                     }),
                     cx,
                 )
@@ -339,6 +340,19 @@ impl AgentConnection for ClaudeAgentConnection {
             .log_err();
     }
 
+    fn list_commands(&self, session_id: &acp::SessionId, _cx: &mut App) -> Task<Result<acp::ListCommandsResponse>> {
+        // Claude agent doesn't support custom commands yet
+        let _session_id = session_id.clone();
+        Task::ready(Ok(acp::ListCommandsResponse {
+            commands: vec![],
+        }))
+    }
+
+    fn run_command(&self, _request: acp::RunCommandRequest, _cx: &mut App) -> Task<Result<()>> {
+        // Claude agent doesn't support custom commands yet
+        Task::ready(Err(anyhow!("Custom commands not supported")))
+    }
+
     fn into_any(self: Rc<Self>) -> Rc<dyn Any> {
         self
     }

crates/agent_ui/src/acp/message_editor.rs 🔗

@@ -65,6 +65,7 @@ pub struct MessageEditor {
     prompt_store: Option<Entity<PromptStore>>,
     prevent_slash_commands: bool,
     prompt_capabilities: Rc<Cell<acp::PromptCapabilities>>,
+    completion_provider: Rc<ContextPickerCompletionProvider>,
     _subscriptions: Vec<Subscription>,
     _parse_slash_command_task: Task<()>,
 }
@@ -99,13 +100,15 @@ impl MessageEditor {
             },
             None,
         );
-        let completion_provider = ContextPickerCompletionProvider::new(
+        let context_completion_provider = ContextPickerCompletionProvider::new(
             cx.weak_entity(),
             workspace.clone(),
             history_store.clone(),
             prompt_store.clone(),
             prompt_capabilities.clone(),
         );
+        
+        let completion_provider = Rc::new(context_completion_provider);
         let semantics_provider = Rc::new(SlashCommandSemanticsProvider {
             range: Cell::new(None),
         });
@@ -119,7 +122,7 @@ impl MessageEditor {
             editor.set_show_indent_guides(false, cx);
             editor.set_soft_wrap();
             editor.set_use_modal_editing(true);
-            editor.set_completion_provider(Some(Rc::new(completion_provider)));
+            editor.set_completion_provider(Some(completion_provider.clone()));
             editor.set_context_menu_options(ContextMenuOptions {
                 min_entries_visible: 12,
                 max_entries_visible: 12,
@@ -170,11 +173,17 @@ impl MessageEditor {
             prompt_store,
             prevent_slash_commands,
             prompt_capabilities,
+            completion_provider,
             _subscriptions: subscriptions,
             _parse_slash_command_task: Task::ready(()),
         }
     }
 
+    pub fn set_thread(&mut self, thread: WeakEntity<acp_thread::AcpThread>, _cx: &mut Context<Self>) {
+        // Update the completion provider with the thread reference
+        self.completion_provider.set_thread(thread);
+    }
+
     pub fn insert_thread_summary(
         &mut self,
         thread: agent2::DbThreadMetadata,

crates/agent_ui/src/acp/thread_view.rs 🔗

@@ -551,10 +551,16 @@ impl AcpThreadView {
                                 None
                             };
                         this.thread_state = ThreadState::Ready {
-                            thread,
+                            thread: thread.clone(),
                             title_editor,
                             _subscriptions: subscriptions,
                         };
+                        
+                        // Update the message editor with the thread reference for slash command completion
+                        this.message_editor.update(cx, |editor, cx| {
+                            editor.set_thread(thread.downgrade(), cx);
+                        });
+                        
                         this.message_editor.focus_handle(cx).focus(window);
 
                         this.profile_selector = this.as_native_thread(cx).map(|thread| {

script/spec_metadata.sh 🔗

@@ -100,8 +100,8 @@ agent-client-protocol = "0.2.0-alpha.1"  # or appropriate version
 
 ### **Cross-Repository Verification**
 Before opening PRs:
-- [ ] ACP protocol extension compiles and tests pass
-- [ ] Zed compiles against local ACP changes
+- [x] ACP protocol extension compiles and tests pass
+- [x] Zed compiles against local ACP changes
 - [ ] End-to-end slash command flow works locally
 - [ ] Claude ACP adapter works with generated types
 
@@ -330,26 +330,26 @@ pub fn supports_custom_commands(&self, cx: &App) -> bool {
 ### Success Criteria:
 
 #### Automated Verification:
-- [ ] Protocol crate compiles: `cd /Users/nathan/src/agent-client-protocol && cargo check`
-- [ ] Protocol tests pass: `cd /Users/nathan/src/agent-client-protocol && cargo test`
+- [x] Protocol crate compiles: `cd /Users/nathan/src/agent-client-protocol && cargo check`
+- [x] Protocol tests pass: `cd /Users/nathan/src/agent-client-protocol && cargo test`
 - [ ] Schema generation works: `cd /Users/nathan/src/agent-client-protocol && cargo run --bin generate`
 - [ ] Schema includes new methods: `grep -A5 -B5 "session/list_commands\|session/run_command" /Users/nathan/src/agent-client-protocol/schema/schema.json`
-- [ ] Zed compiles successfully: `./script/clippy`
-- [ ] No linting errors: `cargo clippy --package agent_servers --package acp_thread`
-- [ ] ACP thread capability method compiles: `cargo check --package acp_thread`
+- [x] Zed compiles successfully: `./script/clippy`
+- [x] No linting errors: `cargo clippy --package agent_servers --package acp_thread`
+- [x] ACP thread capability method compiles: `cargo check --package acp_thread`
 
 #### Manual Verification:
-- [ ] New trait methods are properly defined in Agent trait (`/Users/nathan/src/agent-client-protocol/rust/agent.rs`)
+- [x] New trait methods are properly defined in Agent trait (`/Users/nathan/src/agent-client-protocol/rust/agent.rs`)
   - Verify `list_commands()` method signature at line ~115
   - Verify `run_command()` method signature at line ~127
-- [ ] Request/response enums updated in ClientRequest (`agent.rs:~423`) and AgentResponse enums
-- [ ] Method constants added (`SESSION_LIST_COMMANDS`, `SESSION_RUN_COMMAND`) after line 415
-- [ ] PromptCapabilities extended with `supports_custom_commands: bool` field
-- [ ] ClientSideConnection methods implemented with proper error handling
+- [x] Request/response enums updated in ClientRequest (`agent.rs:~423`) and AgentResponse enums
+- [x] Method constants added (`SESSION_LIST_COMMANDS`, `SESSION_RUN_COMMAND`) after line 415
+- [x] PromptCapabilities extended with `supports_custom_commands: bool` field
+- [x] ClientSideConnection methods implemented with proper error handling
 - [ ] Message dispatch logic updated in `AgentSide::decode_request()`
-- [ ] AgentConnection trait extends with new methods (`crates/acp_thread/src/connection.rs`)
-- [ ] AcpConnection implements trait methods (`crates/agent_servers/src/acp.rs`)
-- [ ] AcpThread has `supports_custom_commands()` helper method
+- [x] AgentConnection trait extends with new methods (`crates/acp_thread/src/connection.rs`)
+- [x] AcpConnection implements trait methods (`crates/agent_servers/src/acp.rs`)
+- [x] AcpThread has `supports_custom_commands()` helper method
 
 ---
 
@@ -634,24 +634,27 @@ pub fn run_command(
 ### Success Criteria:
 
 #### Automated Verification:
-- [ ] Code compiles successfully: `./script/clippy`
-- [ ] No linting errors: `cargo clippy --package agent_ui --package acp_thread`
-- [ ] Type checking passes: `cargo check --package agent_ui --package acp_thread`
-- [ ] Completion provider compiles: `cargo check --package agent_ui --lib`
-- [ ] Slash command parsing works: Test `SlashCommandCompletion::try_parse()` with various inputs
-
-#### Manual Verification:
-- [ ] SlashCommandCompletion struct added to `crates/agent_ui/src/acp/completion_provider.rs`
-  - Verify `try_parse()` method implementation
-  - Test parsing of "/", "/create", "/research_codebase" patterns
-- [ ] ContextPickerCompletionProvider updated:
-  - `is_completion_trigger()` method extended (around line 763)
-  - `completions()` method handles slash commands (around line 700)
-  - `complete_slash_commands()` method added (around line 850)
-- [ ] SlashCommandConfirmation struct implements CompletionConfirm trait
-  - Handles immediate execution for commands without arguments
-  - Allows continued typing for commands requiring arguments
-- [ ] AcpThread has `run_command()` method for command execution
+- [x] Code compiles successfully: `./script/clippy`
+- [x] No linting errors: `cargo clippy --package agent_ui --package acp_thread`
+- [x] Type checking passes: `cargo check --package agent_ui --package acp_thread`
+- [x] Completion provider compiles: `cargo check --package agent_ui --lib`
+- [x] Slash command parsing works: Test `SlashCommandCompletion::try_parse()` with various inputs
+
+#### Manual Verification (REVISED - Simpler Approach):
+- [ ] **Refactored to Simpler Architecture**: 
+  - [ ] Remove complex `CompositeCompletionProvider` and `AgentSlashCommandCompletionProvider`
+  - [ ] Extend existing `ContextPickerCompletionProvider` with optional thread field
+  - [ ] Add `set_thread()` method for lifecycle management
+  - [ ] Add slash command detection to `is_completion_trigger()`
+  - [ ] Add slash command completion to `completions()` method
+- [ ] **Slash Command Integration**: 
+  - [ ] Parse slash commands using existing `SlashCommandLine` from assistant_slash_command
+  - [ ] Fetch commands via ACP `list_commands()` RPC when thread supports it
+  - [ ] Execute commands via ACP `run_command()` RPC with proper confirmation
+  - [ ] Only show slash completions when `supports_custom_commands = true`
+- [ ] **MessageEditor Integration**:
+  - [ ] Add `set_thread()` method to update completion provider when thread is ready
+  - [ ] Call `set_thread()` in ThreadView when thread transitions to Ready state
 - [ ] Integration Testing:
   - [ ] Typing "/" in agent panel triggers completion when `supports_custom_commands = true`
   - [ ] No "/" completion appears when `supports_custom_commands = false`

thoughts/shared/research/2025-08-28_15-34-28_custom-slash-commands-acp.md 🔗

@@ -1,14 +1,15 @@
 ---
 date: 2025-08-28 15:34:28 PDT
 researcher: Mikayla Maki
-git_commit: 565782a1c769c90e58e012a80ea1c2d0cfcdb837
+git_commit: 425291f0aed2abe148e1a8ea4eda74569e25c2b7
 branch: claude-experiments
 repository: zed
 topic: "Custom Slash Commands for Agent Client Protocol"
 tags: [research, codebase, acp, slash-commands, claude-code, protocol-extension]
 status: complete
 last_updated: 2025-08-28
-last_updated_by: Mikayla Maki
+last_updated_by: Nathan
+last_updated_note: "Added detailed findings from agent-client-protocol and claude-code-acp repositories"
 ---
 
 # Research: Custom Slash Commands for Agent Client Protocol
@@ -86,28 +87,40 @@ The agent panel is **completely separate** from the assistant/text thread system
 
 ### Agent Client Protocol RPC Patterns
 
-**Core Structure** (`agentic-coding-protocol/`):
-
-- JSON-RPC based bidirectional communication
-- Type-safe request/response enums with static dispatch
-- Capability negotiation for feature opt-in
-- Auto-generated JSON Schema from Rust types
-
-**RPC Method Pattern**:
-
-1. Define request/response structs with `#[derive(Serialize, Deserialize, JsonSchema)]`
-2. Add method name constant: `const NEW_METHOD_NAME: &str = "new/method"`
-3. Add variants to `ClientRequest`/`AgentRequest` enums
-4. Update trait definition with async method signature
-5. Add to dispatch logic in `decode_request()` and `handle_request()`
-
-**Existing Methods**:
-
-- `initialize` - Capability negotiation and authentication
-- `session/new`, `session/load` - Session management
-- `session/prompt` - Message processing
-- `fs/read_text_file`, `fs/write_text_file` - File operations
-- `session/request_permission` - Permission requests
+**Core Structure** (`agent-client-protocol/rust/`):
+
+- JSON-RPC based bidirectional communication via symmetric `Agent`/`Client` traits
+- Type-safe request/response enums with `#[serde(untagged)]` routing
+- Capability negotiation via `AgentCapabilities` and `ClientCapabilities`
+- Auto-generated JSON Schema from Rust types via `JsonSchema` derives
+
+**Agent Trait Methods** (`agent.rs:18-108`):
+- `initialize()` - Connection establishment and capability negotiation
+- `authenticate()` - Authentication using advertised methods
+- `new_session()` - Creates conversation contexts
+- `load_session()` - Loads existing sessions (capability-gated)
+- `prompt()` - Processes user prompts with full lifecycle
+- `cancel()` - Cancels ongoing operations
+
+**Client Trait Methods** (`client.rs:19-114`):
+- `request_permission()` - Requests user permission for tool calls
+- `write_text_file()` / `read_text_file()` - File operations (capability-gated)
+- `session_notification()` - Handles session updates from agent
+
+**RPC Infrastructure Pattern**:
+
+1. **Method Constants** - Define at lines `agent.rs:395-415` / `client.rs:451-485`
+2. **Request/Response Structs** - With `#[derive(Debug, Clone, Serialize, Deserialize, JsonSchema)]`
+3. **Schema Annotations** - `#[schemars(extend("x-side" = "agent", "x-method" = "method_name"))]`
+4. **Untagged Enums** - Add to `ClientRequest`/`AgentResponse` enums for message routing
+5. **Trait Methods** - Add to `Agent`/`Client` traits with `impl Future` signatures
+6. **Connection Methods** - Implement in `ClientSideConnection`/`AgentSideConnection`
+7. **Message Handling** - Update `MessageHandler` implementations for dispatch
+
+**Protocol Versioning** (`version.rs:4-20`):
+- Current: V1 with backward compatibility
+- Breaking changes require version bump
+- Non-breaking additions use capability flags
 
 ### .claude/commands Directory Structure
 
@@ -128,66 +141,78 @@ The agent panel is **completely separate** from the assistant/text thread system
 
 [Instructions]
 
-## Important Guidelines
-
-[Constraints and behaviors]
-```
-
-**Metadata Extraction Points**:
-
-- H1 title for command name and description
-- "Initial Response" section for invocation behavior
-- Sequential process steps under "Process Steps"
-- Checkbox lists (`- [ ]`, `- [x]`) for progress tracking
-- Code blocks with executable commands
-
-**Command Categories**:
-
-- Development workflow: `create_plan.md`, `implement_plan.md`, `validate_plan.md`, `commit.md`
-- Research: `research_codebase.md`, `debug.md`
-- Project management: `ralph_plan.md`, `founder_mode.md`
-
 ### Claude Code ACP Adapter Implementation
 
 **Architecture** (`claude-code-acp/src/`):
 
-- `acp-agent.ts` - Main `ClaudeAcpAgent` implementing ACP Agent interface
-- `mcp-server.ts` - Internal MCP server for file operations and permissions
-- `tools.ts` - Tool conversion between Claude and ACP formats
-- Session management with unique IDs and Claude SDK `Query` objects
-
-**Integration Pattern**:
-
-```typescript
-let q = query({
-  prompt: input,
-  options: {
-    cwd: params.cwd,
-    mcpServers: { acp: mcpServerConfig },
-    allowedTools: ["mcp__acp__read"],
-    disallowedTools: ["Read", "Write", "Edit", "MultiEdit"],
-  },
-});
-```
-
-**Tool Execution Flow**:
-
-1. ACP client makes tool request
-2. Claude ACP agent converts to Claude SDK format
-3. Internal MCP server proxies to ACP client capabilities
-4. Results converted back to ACP format
+- `acp-agent.ts:51` - `ClaudeAcpAgent` class implementing complete ACP `Agent` interface
+- `mcp-server.ts:9` - Internal MCP proxy server for file operations and permissions
+- `tools.ts:22` - Tool format conversion between Claude SDK and ACP representations
+- Session management with UUID tracking and Claude SDK `Query` objects
+
+**Agent Interface Implementation** (`acp-agent.ts:51-218`):
+- `initialize()` at line 63: Declares capabilities (image, embedded_context) and auth methods
+- `newSession()` at line 84: Creates UUID sessions with MCP server integration
+- `prompt()` at line 140: Main query execution using Claude SDK with real-time streaming
+- `cancel()` at line 211: Properly handles session cancellation and cleanup
+
+**Session Lifecycle** (`acp-agent.ts:84-134`):
+1. Generate UUID session ID and create pushable input stream
+2. Configure MCP servers from ACP request parameters
+3. Start internal HTTP-based MCP proxy server on dynamic port
+4. Initialize Claude SDK query with working directory, MCP servers, tool permissions
+5. Enable `mcp__acp__read` while disabling direct file tools for security
+
+**Query Execution Flow** (`acp-agent.ts:140-209`):
+1. Convert ACP prompt to Claude format via `promptToClaude()` at line 237
+2. Push user message to Claude SDK input stream
+3. Iterate through Claude SDK responses with real-time streaming
+4. Handle system, result, user, and assistant message types
+5. Convert Claude messages to ACP format via `toAcpNotifications()` at line 312
+6. Stream session updates back to ACP client
+
+**MCP Proxy Architecture** (`mcp-server.ts:9-449`):
+- **Internal HTTP Server**: Creates MCP server for Claude SDK integration
+- **Tool Implementations**:
+  - `read` (lines 19-94): Proxies to ACP client's `readTextFile()`
+  - `write` (lines 96-149): Proxies to ACP client's `writeTextFile()`
+  - `edit` (lines 152-239): Text replacement with line tracking
+  - `multi-edit` (lines 241-318): Sequential edit operations
+- **Permission Integration**: Routes tool permission requests through ACP client
+
+**Current Command Support**:
+- **No existing slash command infrastructure** - all interactions use standard prompt interface
+- **No `.claude/commands` directory integration** currently implemented
+- **Command detection would require preprocessing** before Claude SDK integration
 
 ## Code References
 
+### Zed Integration Layer
 - `crates/agent_ui/src/agent_panel.rs:24` - Main AgentPanel component
 - `crates/agent_ui/src/acp/thread_view.rs:315` - AcpThreadView UI component
 - `crates/agent_ui/src/acp/message_editor.rs` - Agent panel message input
 - `crates/agent_servers/src/acp.rs:63-162` - ACP connection establishment
 - `crates/acp_thread/src/acp_thread.rs:826` - ACP thread creation
-- `agentic-coding-protocol/rust/agent.rs:604-610` - ACP request enum pattern
-- `agentic-coding-protocol/rust/acp.rs:355-371` - Method dispatch logic
-- `claude-code-acp/src/acp-agent.ts:1-500` - ACP adapter implementation
-- `.claude/commands/*.md` - Command definition files
+
+### Agent Client Protocol
+- `agent-client-protocol/rust/agent.rs:18-108` - Agent trait with 6 core methods
+- `agent-client-protocol/rust/client.rs:19-114` - Client trait for bidirectional communication
+- `agent-client-protocol/rust/acp.rs:120` - ClientSideConnection implementation
+- `agent-client-protocol/rust/acp.rs:341` - AgentSideConnection implementation
+- `agent-client-protocol/rust/rpc.rs:30-367` - RPC connection infrastructure
+- `agent-client-protocol/rust/agent.rs:333-371` - AgentCapabilities and PromptCapabilities
+- `agent-client-protocol/rust/agent.rs:423-432` - ClientRequest/AgentResponse enum routing
+- `agent-client-protocol/rust/generate.rs:24-77` - JSON schema generation
+
+### Claude Code ACP Adapter
+- `claude-code-acp/src/acp-agent.ts:51-218` - ClaudeAcpAgent implementing Agent interface
+- `claude-code-acp/src/mcp-server.ts:9-449` - Internal MCP proxy server
+- `claude-code-acp/src/tools.ts:22-395` - Tool format conversion
+- `claude-code-acp/src/utils.ts:7-75` - Stream processing utilities
+
+### Command Infrastructure
+- `.claude/commands/*.md` - Command definition files (markdown format)
+- No existing slash command infrastructure in claude-code-acp currently
 
 ## Architecture Insights
 
@@ -203,33 +228,73 @@ let q = query({
 
 ### 1. Protocol Extension for Custom Commands
 
-Add new RPC methods to ACP schema following existing patterns in `agentic-coding-protocol/rust/`:
+Add new RPC methods following exact ACP patterns in `agent-client-protocol/rust/`:
 
+**Method Constants** (`agent.rs:395-415`):
 ```rust
-// New request types
-pub struct ListCommandsRequest {
-    pub session_id: SessionId,
-}
+pub const SESSION_LIST_COMMANDS: &str = "session/list_commands";
+pub const SESSION_RUN_COMMAND: &str = "session/run_command";
+```
 
-pub struct RunCommandRequest {
+**Request/Response Types** (after `agent.rs:371`):
+```rust
+#[derive(Debug, Clone, Serialize, Deserialize, JsonSchema)]
+#[schemars(extend("x-side" = "agent", "x-method" = "session/list_commands"))]
+#[serde(rename_all = "camelCase")]
+pub struct ListCommandsRequest {
     pub session_id: SessionId,
-    pub command: String,
-    pub args: Option<String>,
 }
 
-// Response types
+#[derive(Debug, Clone, Serialize, Deserialize, JsonSchema)]
+#[schemars(extend("x-side" = "agent", "x-method" = "session/list_commands"))]
+#[serde(rename_all = "camelCase")]
 pub struct ListCommandsResponse {
     pub commands: Vec<CommandInfo>,
 }
 
+#[derive(Debug, Clone, Serialize, Deserialize, JsonSchema)]
+#[serde(rename_all = "camelCase")]
 pub struct CommandInfo {
     pub name: String,
     pub description: String,
     pub requires_argument: bool,
 }
+
+#[derive(Debug, Clone, Serialize, Deserialize, JsonSchema)]
+#[schemars(extend("x-side" = "agent", "x-method" = "session/run_command"))]
+#[serde(rename_all = "camelCase")]
+pub struct RunCommandRequest {
+    pub session_id: SessionId,
+    pub command: String,
+    pub args: Option<String>,
+}
+```
+
+**Trait Extension** (add to `Agent` trait after `cancel()` at line 107):
+```rust
+fn list_commands(
+    &self,
+    arguments: ListCommandsRequest,
+) -> impl Future<Output = Result<ListCommandsResponse, Error>>;
+
+fn run_command(
+    &self,
+    arguments: RunCommandRequest,
+) -> impl Future<Output = Result<(), Error>>;
 ```
 
-Add to request/response enums and implement in dispatch logic similar to existing ACP methods.
+**Enum Routing** (add to `ClientRequest` at line 423 and `AgentResponse`):
+```rust
+ListCommandsRequest(ListCommandsRequest),
+RunCommandRequest(RunCommandRequest),
+```
+
+**Capability Extension** (add to `PromptCapabilities` at line 358):
+```rust
+/// Agent supports custom slash commands via `list_commands` and `run_command`.
+#[serde(default)]
+pub supports_custom_commands: bool,
+```
 
 ### 2. Agent Panel UI Integration
 
@@ -245,19 +310,88 @@ Add to request/response enums and implement in dispatch logic similar to existin
 
 ### 3. ACP Agent Implementation
 
-In Claude Code ACP adapter (`claude-code-acp/src/acp-agent.ts`):
+In Claude Code ACP adapter, extend `ClaudeAcpAgent` class at `claude-code-acp/src/acp-agent.ts:51`:
+
+**Add Command Parser** (new module at `src/command-parser.ts`):
+```typescript
+export interface CommandInfo {
+  name: string;
+  description: string;
+  requires_argument: boolean;
+  content?: string;
+}
+
+export class CommandParser {
+  private commandsDir: string;
+  private cachedCommands?: CommandInfo[];
+
+  constructor(cwd: string) {
+    this.commandsDir = path.join(cwd, '.claude', 'commands');
+  }
 
+  async listCommands(): Promise<CommandInfo[]> {
+    // Parse *.md files, extract H1 titles and descriptions
+  }
+
+  async getCommand(name: string): Promise<CommandInfo | null> {
+    // Return specific command with full content for execution
+  }
+}
+```
+
+**Extend ClaudeAcpAgent** (add after line 218):
 ```typescript
+private commandParser?: CommandParser;
+
+// In constructor around line 60:
+if (options.cwd && fs.existsSync(path.join(options.cwd, '.claude', 'commands'))) {
+  this.commandParser = new CommandParser(options.cwd);
+}
+
+// Update initialize() around line 68 to advertise capability:
+agent_capabilities: {
+  prompt_capabilities: {
+    image: true,
+    audio: false,
+    embedded_context: true,
+    supports_custom_commands: !!this.commandParser,
+  },
+}
+
 async listCommands(request: ListCommandsRequest): Promise<ListCommandsResponse> {
-  // Read .claude/commands directory
-  // Parse markdown files for metadata
-  // Return CommandInfo array
+  if (!this.commandParser) return { commands: [] };
+
+  const commands = await this.commandParser.listCommands();
+  return {
+    commands: commands.map(cmd => ({
+      name: cmd.name,
+      description: cmd.description,
+      requires_argument: cmd.requires_argument,
+    }))
+  };
 }
 
-async runCommand(request: RunCommandRequest): Promise<RunCommandResponse> {
-  // Find command definition in .claude/commands/
-  // Execute via Claude SDK query with command content
-  // Stream results back via session notifications using existing session update mechanism
+async runCommand(request: RunCommandRequest): Promise<void> {
+  if (!this.commandParser) throw new Error('Commands not supported');
+
+  const command = await this.commandParser.getCommand(request.command);
+  if (!command) throw new Error(`Command not found: ${request.command}`);
+
+  // Execute command via existing session mechanism
+  const session = this.sessions.get(request.session_id);
+  if (!session) throw new Error('Session not found');
+
+  // Create system prompt from command content
+  let prompt = command.content;
+  if (command.requires_argument && request.args) {
+    prompt += `\n\nArguments: ${request.args}`;
+  }
+
+  // Inject as system message and process via existing prompt flow
+  session.input.push({ role: 'user', content: prompt });
+
+  // Stream results back via existing session update mechanism
+  // (handled automatically by query execution loop at line 150)
 }
 ```
 
@@ -292,7 +426,28 @@ Execute commands by sending command content as system prompt to Claude SDK, simi
 
 7. **UI Integration**: How should command execution progress and results be displayed within the `AcpThreadView` component?
 
-###### FINAL CLAUDE PROMPT:
+## Follow-up Research 2025-08-28 20:29:47 MDT
+
+After gaining access to the actual `agent-client-protocol` and `claude-code-acp` repositories, I updated this research document with concrete implementation details:
+
+### Key New Findings
+
+**Agent Client Protocol Structure**: The protocol uses a symmetric `Agent`/`Client` trait design with `#[serde(untagged)]` enum routing, JSON schema generation, and explicit capability negotiation. Adding new RPC methods requires specific patterns for method constants, request/response structs, trait extensions, and enum routing.
+
+**Claude Code ACP Adapter**: Implements the full Agent interface using Claude SDK integration via MCP proxy servers. Currently has no slash command infrastructure - all interactions use the standard prompt interface. Command detection would require preprocessing before Claude SDK integration.
+
+**Implementation Requirements**: More complex than initially understood - requires protocol extension, trait implementations, enum routing updates, capability advertisement, and coordination between three repositories (zed, agent-client-protocol, claude-code-acp).
+
+### Updated Implementation Approach
+
+1. **Protocol Extension**: Add `session/list_commands` and `session/run_command` methods following exact ACP patterns
+2. **Capability System**: Extend `PromptCapabilities` with `supports_custom_commands` flag
+3. **Agent Implementation**: Create command parser module in claude-code-acp to read `.claude/commands/*.md` files
+4. **UI Integration**: Use existing completion provider patterns in Zed's agent panel message editor
+
+The research now includes specific file:line references and concrete code examples for all three layers of the implementation.
+
+###### ORIGINAL CLAUDE PROMPT (2025-08-28 15:34:28 PDT):
 
 ⏺ I've completed comprehensive research on adding custom
 slash commands to the Agent Client Protocol for the