Merge pull request #3 from nikomatsakis/introduce-eliza

Introduce "elizacp"

Author: nikomatsakis

Cargo.lock

@@ -3,6 +3,7 @@ members = [
     "src/sacp-proxy",
     "src/sacp-conductor",
     "src/sacp",
+    "src/elizacp",
 ]
 resolver = "2"
 

Cargo.toml

@@ -26,6 +26,7 @@ This repository contains three core crates:
 - **[`sacp`](./src/sacp/)** - Core protocol types and traits for building clients and agents
 - **[`sacp-proxy`](./src/sacp-proxy/)** - Framework for building proxy components
 - **[`sacp-conductor`](./src/sacp-conductor/)** - Binary that orchestrates proxy chains
+- **[`elizacp`](./src/elizacp/)** - Example ACP agent implementing the classic Eliza chatbot (useful for testing)
 
 ## Documentation
 

README.md

@@ -0,0 +1,34 @@
+[package]
+name = "elizacp"
+version = "0.1.0"
+edition = "2024"
+description = "Classic Eliza chatbot as an ACP agent for testing"
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/agent-client-protocol/symposium-acp"
+keywords = ["acp", "agent", "eliza", "testing"]
+categories = ["development-tools"]
+authors = ["Niko Matsakis <[email protected]>"]
+readme = "README.md"
+
+[[bin]]
+name = "elizacp"
+path = "src/main.rs"
+
+[dependencies]
+sacp = { version = "0.1.0", path = "../sacp" }
+agent-client-protocol-schema.workspace = true
+anyhow.workspace = true
+clap.workspace = true
+futures.workspace = true
+rand = "0.8"
+regex = "1.10"
+serde.workspace = true
+serde_json.workspace = true
+tokio.workspace = true
+tokio-util.workspace = true
+tracing.workspace = true
+tracing-subscriber.workspace = true
+uuid.workspace = true
+
+[dev-dependencies]
+expect-test.workspace = true

src/elizacp/Cargo.toml

@@ -0,0 +1,69 @@
+# elizacp
+
+A classic Eliza chatbot implemented as an ACP (Agent-Client Protocol) agent.
+
+## Overview
+
+Elizacp provides a simple, predictable agent implementation that's useful for:
+
+- **Testing ACP clients** - Lightweight agent with deterministic pattern-based responses
+- **Protocol development** - Verify ACP implementations without heavy AI infrastructure
+- **Learning ACP** - Clean example of implementing the Agent-Client Protocol
+
+## Features
+
+- **Classic Eliza patterns** - Pattern matching and reflection-based responses
+- **Full ACP support** - Session management, initialization, and prompt handling
+- **Per-session state** - Each session maintains its own Eliza instance
+- **Extensible patterns** - Easy to add new response patterns (including future tool use triggers)
+
+## Usage
+
+### Running the agent
+
+```bash
+# Build and run
+cargo run -p elizacp
+
+# With debug logging
+cargo run -p elizacp -- --debug
+```
+
+The agent communicates over stdin/stdout using JSON-RPC, following the ACP specification.
+
+### Testing with an ACP client
+
+Elizacp responds to:
+
+1. **Initialize requests** - Returns capabilities
+2. **New/Load session requests** - Creates session state
+3. **Prompt requests** - Responds with Eliza-style conversational replies
+
+Example conversation:
+```
+User: Hello
+Eliza: Hello. How are you feeling today?
+
+User: I am sad
+Eliza: Do you often feel sad?
+
+User: I feel worried about my father
+Eliza: Tell me more about your family.
+```
+
+## Implementation
+
+- `eliza.rs` - Pattern matching engine with classic Eliza responses
+- `main.rs` - ACP agent implementation over stdio
+
+## Architecture
+
+The agent maintains a `HashMap<SessionId, Eliza>` to track per-session state. Each session gets its own Eliza instance with independent conversation state.
+
+## Future Extensions
+
+The pattern database structure is designed to support:
+- Tool use triggers (e.g., "what's the weather" → tool call)
+- Custom response patterns
+- Conversation history tracking
+- Multi-turn context awareness