HippoDid MCP Server
MCP (Model Context Protocol) server for HippoDid — connects Claude Code, Claude Desktop, ChatGPT, Gemini CLI, Codex CLI, Cursor, and any MCP-compatible client to persistent AI character memory.
What is HippoDid?
HippoDid is a cloud memory infrastructure for AI agents. It stores structured memories (preferences, decisions, skills, relationships) in a searchable database and retrieves them across sessions, tools, and AI providers. Write a memory in Claude Code, recall it in ChatGPT. Switch from Cursor to Gemini — your agent's memory travels with it.
Key features:
- Cross-platform memory — same memories accessible from any MCP client or ChatGPT via OAuth
- Structured extraction — raw text is automatically parsed into categorized facts with salience scores
- Temporal decay — memories fade naturally by category (skills are evergreen, events fade in 14 days)
- Character scoping — each agent/project gets its own memory namespace
- BYOK AI — bring your own OpenAI, Anthropic, or Gemini key for extraction
Quick Start
1. Get an API Key
Sign up at hippodid.com and create an API key from your dashboard.
2. Download the JAR
Download the latest release from GitHub Releases.
3. Configure Claude Desktop
Add to your Claude Desktop config (~/Library/Application Support/Claude/claude_desktop_config.json on macOS):
{
"mcpServers": {
"hippodid": {
"command": "java",
"args": ["-jar", "/path/to/hippodid-mcp-server-1.1.0.jar"],
"env": {
"HIPPODID_API_KEY": "hd_key_your_key_here",
"HIPPODID_CHARACTER_ID": "your-character-uuid"
}
}
}
}
4. Start Using
Ask Claude to remember things, search memories, sync files, and more.
MCP Tools
| Tool | Description |
|---|---|
create_character | Create a new character to store memories for |
list_characters | List all characters accessible to you |
add_memory | Add a memory via the AUDN pipeline (rule-based salience + dedup) |
add_memory_direct | Write a memory directly, bypassing AUDN pipeline (Starter+ tier) |
search_memories | Hybrid semantic + keyword search across memories |
sync_file | Sync a local file to the HippoDid cloud |
import_document | Import a document and extract memories (Starter+ tier) |
list_synced_files | List files synced to the cloud for a character |
get_sync_status | Get sync status summary for a character |
export_character | Export all memories for a character as Markdown |
add_watch_path | Sync a file and register the path for background tracking |
list_watch_paths | List all watched file paths in this session |
force_sync | Force an immediate sync of all watched paths |
configure_ai | Configure tenant BYOK AI providers |
test_ai_config | Test connectivity of saved AI provider configuration |
Environment Variables
| Variable | Required | Default | Description |
|---|---|---|---|
HIPPODID_API_KEY | Yes | — | Your HippoDid API key |
HIPPODID_CHARACTER_ID | No | — | Default character UUID for background sync |
HIPPODID_BASE_URL | No | https://api.hippodid.com | API base URL |
MCP_SYNC_INTERVAL | No | 300 | Background sync interval in seconds |
MCP_AUTO_CAPTURE | No | false | Disable background watcher (AI handles sync) |
MCP_AUTO_RECALL | No | false | Disable background hydration (AI handles download) |
MCP_RECALL_CACHE_TTL | No | 120 | Search result cache TTL in seconds |
Architecture
Claude Desktop → stdio (JSON-RPC) → McpServerRunner → HippoDidClient → HTTP → HippoDid REST API
The MCP server uses the hippodid-spring-boot-starter to communicate with the HippoDid REST API over HTTP. All authentication and tenant isolation is handled server-side via Bearer tokens.
Building from Source
Requires Java 21+ and Maven 3.8+.
mvn clean package -DskipTests
java -jar target/hippodid-mcp-server-1.1.0.jar
Versioning
The MCP server version matches the hippodid-spring-boot-starter version. Both must be at the same version for compatibility.
License
Apache License 2.0 — see LICENSE.