XMemo Hermes Agent Memory Provider Plugin

XMemo is an identity-aware memory layer for AI agents: one persistent, user-owned memory space that works across ChatGPT, Copilot, Claude, Codex, Gemini, and here — Hermes Agent. Every memory entry knows who wrote it, so you can recall, audit, and control context without confusion or spillover.

This plugin connects Hermes Agent to your XMemo account, giving the agent durable memory that survives sessions and long-running workflows, with per-profile isolation.

Agent-readable summary

Use this section when a setup agent, package index, marketplace crawler, or Hermes-aware assistant needs to classify the integration quickly.

Field	Value
Package	hermes-xmemo
Hermes plugin name	xmemo
Runtime role	Native Hermes memory provider
Recommended mode	hermes_plugin_preferred
XMemo service	https://xmemo.dev
XMemo MCP fallback	https://xmemo.dev/mcp
Agent discovery	https://xmemo.dev/.well-known/agent-discovery.json
Hermes config endpoint	https://xmemo.dev/v1/mcp/config/hermes
Repository	https://github.com/yonro/hermes-xmemo-plugin
ChatGPT bridge	ChatGPT can connect to XMemo through the hosted MCP/OAuth path; user-approved memories saved there can be recalled by Hermes through this plugin.

If the active runtime is Hermes Agent, prefer this native plugin over raw MCP configuration. The plugin participates in Hermes' memory lifecycle: pre-turn recall, native memory mirroring, working state, optional workflow tools, and session-end snapshots. Use the hosted MCP endpoint only as a portable fallback or for non-Hermes MCP clients.

Shared memory with ChatGPT

XMemo gives Hermes a way to work with the same user-owned cloud memory that can also be connected from ChatGPT. When a user saves useful ChatGPT brainstorms, project decisions, preferences, research notes, or handoff context into XMemo, Hermes can later recall that context through this native memory provider.

This is especially useful for long-running work: ChatGPT can help shape the idea, XMemo stores the durable context under the user's account, and Hermes can continue with the same memory layer during agent runs. This does not mean the plugin reads ChatGPT's built-in native memory directly. It reads XMemo memories that the user explicitly saved or authorized through the XMemo connection. Marketplace or official-connection claims should be made only when supported by public listing or review evidence.

What it does

• Cross-agent recall — Hermes prefetches relevant XMemo context from all visible memories in your XMemo account, including memories written by other connected agents.
• Semantic search — ask the agent to search saved facts with natural language (xmemo_search); results include provenance such as self or other_agent when XMemo returns it.
• Durable fact storage — store explicit facts, preferences, and decisions (xmemo_remember).
• Working state with TTL — save active task, next action, or blocker so future sessions can resume (xmemo_update_state).
• Built-in memory mirroring — when Hermes' native memory tool writes, the same fact is mirrored to XMemo.
• Session snapshots — captures a restart snapshot at session end for later restoration by compatible XMemo workflows.
• Reminders & timeline — optional workflow tools for TODOs and timeline events (opt-in via config).
• Hermes write scoping — new Hermes-authored memories are written to the configured Hermes scope so provenance stays clear.
• Resilient by default — circuit breaker pauses API calls after consecutive failures; background prefetch/sync never block the chat.

Install

Hermes looks for memory provider plugins in $HERMES_HOME/plugins/<name>/. The default HERMES_HOME is ~/.hermes.

XMemo CLI setup (recommended)

npm install -g @xmemo/client
xmemo login
xmemo setup hermes

xmemo setup hermes installs or updates hermes-xmemo, runs hermes-xmemo install, and syncs the shared XMemo credential to Hermes.

To install to a non-default Hermes home:

xmemo setup hermes --hermes-home /path/to/your/hermes-home

pip install

Use this lower-level path when you do not want @xmemo/client to manage setup:

pip install hermes-xmemo
hermes-xmemo install
hermes memory setup xmemo

One-liner (no pip)

curl -fsSL https://raw.githubusercontent.com/yonro/hermes-xmemo-plugin/main/install-remote.sh | bash
hermes memory setup xmemo

Using install.sh (if you already cloned)

cd hermes-xmemo-plugin
bash install.sh

Manual install

# Remove any previous install first to avoid nested directories.
rm -rf "${HERMES_HOME:-$HOME/.hermes}/plugins/xmemo"
mkdir -p "${HERMES_HOME:-$HOME/.hermes}/plugins"
cp -r src/hermes_xmemo/xmemo "${HERMES_HOME:-$HOME/.hermes}/plugins/"

Configure

Recommended shared-credential setup:

xmemo login
xmemo setup hermes

This uses the same user-scoped credential as @xmemo/client, syncs it to Hermes' existing $HERMES_HOME/.env XMEMO_KEY location for compatibility, and installs/updates the native Hermes plugin. Hosted MCP is not installed by default; use xmemo setup hermes --with-mcp only when you want that fallback.

The original Hermes-native setup remains supported:

hermes memory setup xmemo

If xmemo login or xmemo token add --from-stdin has already stored a shared credential, the setup wizard can reuse it. If not, it asks for your XMemo token and writes XMEMO_KEY to $HERMES_HOME/.env as before.

Or manually:

hermes config set memory.provider xmemo
echo "XMEMO_KEY=your-token" >> "${HERMES_HOME:-$HOME/.hermes}/.env"

Requirements

• Hermes Agent (the plugin is loaded by Hermes at runtime)
• httpx (already a dependency of Hermes)
• XMemo service token from xmemo.dev

How it works

1. Before the turn — Hermes calls prefetch() to retrieve relevant XMemo context across visible memories in your XMemo account and injects it into the conversation.
2. During the turn — the agent can call explicit XMemo tools (xmemo_search, xmemo_remember, etc.).
3. After the turn — high-signal turns can be recorded to the XMemo timeline if capture_timeline is enabled.
4. Session end — a restart snapshot is captured for later restoration by compatible XMemo workflows.

Automatic prefetch, turn sync, and session snapshots run in the background. Explicit tool calls and memory mirroring use bounded timeouts, with a circuit breaker protecting Hermes from repeated failures.

Configure

Most users do not need this section. Advanced settings are available in $HERMES_HOME/xmemo.json:

Key	Default	Description
agent_id	hermes	Agent family identifier
agent_instance_id	auto-generated	Stable, opaque install identifier
bucket	work	Storage namespace for new Hermes-authored writes
scope	hermes/default	Scope for new Hermes-authored writes
read_bucket	%	Bucket filter for recall/search (% = all visible buckets)
read_scope	unset	Scope filter for recall/search (unset = all visible scopes)
timeout_seconds	5.0	REST request timeout
prefetch_max_items	5	Max context items per recall
prefetch_max_tokens	900	Max context tokens per recall
enable_workflow_tools	false	Expose reminder/event tools
enable_destructive_tools	false	Expose xmemo_forget
capture_timeline	false	Record high-signal turns to timeline

Environment variables

You can override most settings via environment variables (useful for CI or containerized setups):

Variable	Overrides
XMEMO_KEY	API key (highest priority; MEMORY_OS_API_KEY and MEMORY_OS_MCP_TOKEN are also accepted)
XMEMO_AGENT_ID	agent_id
XMEMO_AGENT_INSTANCE_ID	agent_instance_id
XMEMO_BUCKET	bucket
XMEMO_SCOPE	scope
XMEMO_READ_BUCKET	read_bucket
XMEMO_READ_SCOPE	read_scope
XMEMO_TIMEOUT_SECONDS	timeout_seconds
XMEMO_PREFETCH_MAX_ITEMS	prefetch_max_items
XMEMO_PREFETCH_MAX_TOKENS	prefetch_max_tokens

Tools

Default tools

These tools are always available:

Tool	Description
xmemo_recall_context	Build a bounded, ranked context pack
xmemo_search	Semantic search over XMemo memories
xmemo_remember	Save a durable fact
xmemo_update_state	Save active task / next action / blocker with TTL

Optional workflow tools

Set enable_workflow_tools: true in xmemo.json to expose:

Tool	Description
xmemo_record_event	Append a timeline event or milestone
xmemo_create_reminder	Create a TODO / action item
xmemo_list_reminders	List open or completed reminders
xmemo_complete_reminder	Mark a reminder as completed

Optional destructive tool

Set enable_destructive_tools: true to expose:

Tool	Description
xmemo_forget	Delete a memory by exact id

Privacy & security

• API keys live in $HERMES_HOME/.env or the user-scoped @xmemo/client credentials.json, never in xmemo.json.
• Credential lookup is backwards compatible: explicit Hermes/process environment variables win, then the shared @xmemo/client credential file is used as a fallback.
• xmemo_forget requires an exact memory id and is disabled by default.
• Automatic timeline writes are disabled by default. When enabled, only high-signal turns (decisions, preferences, blockers, etc.) are recorded.
• Built-in memory tool writes are mirrored to XMemo only when the provider is active.
• Prefetch cache is isolated per session, so concurrent gateway sessions cannot cross-contaminate recall context.

Reliability, Local Cache & Outbox

To improve availability and reduce data-loss risk during temporary XMemo API outages, the plugin implements a local reliability layer using a SQLite database (xmemo_cache.db located in $HERMES_HOME).

1. Read Cache Fallback

• Authoritative Cloud Priority: When online, the plugin always queries the XMemo cloud first to ensure absolute freshness.
• Lightweight Caching: Successful query results (xmemo_search, xmemo_recall_context, and background prefetches) are cached locally with a 5-minute fresh TTL.
• Stale Fallback: If the XMemo cloud is unreachable (transient connection failures, timeouts, or HTTP 5xx errors), the plugin automatically falls back to the local cache, provided the cached data is less than 24 hours old (max_stale_until). Fallback results are returned with stale: true and source: "cache" markers to inform the agent of their status.

2. Write Outbox & Idempotency

• Failover Queueing: When a write operation (e.g., saving a fact, updating state, recording an event) fails due to a transient network error, it is automatically enqueued into a local outbox.
• Outbox Status Routing:
  • Idempotent Writes (xmemo_remember, xmemo_update_state): Enqueued as 'pending' and automatically replayed by a background sync daemon using exponential backoff (up to 5 retries, capped at a maximum delay of 1 hour).
  • Non-Idempotent Writes (xmemo_record_event, xmemo_create_reminder, etc.): By default, these enter a 'held' status and are not replayed automatically (unless enable_non_idempotent_replay: true is set in xmemo.json), protecting the server from duplicate entries.
• Idempotency Standards: Every write operation generates a stable, unique idempotency key (UUID) at initiation. This key is preserved and sent in the Idempotency-Key and X-Idempotency-Key headers, as well as the JSON body, on all retries and replays, allowing the XMemo server to deduplicate requests.
• Dead-Lettering: If an outbox write fails with a permanent non-transient error (e.g., HTTP 4xx validation or auth errors) or exhausts all 5 retry attempts, it is immediately moved to 'failed' (dead-lettered) status with the error message recorded in the database.

3. Privacy, Retention & Diagnostics

• Payload Security:

  [!WARNING] The local xmemo_cache.db database file stores copies of cached recall responses and queued outbox payloads in plain-text JSON. No credentials or API keys are ever cached or written to this database. To protect this sensitive data, secure the $HERMES_HOME directory and restrict file access to the owner process.

• Database Retention & Cleanup:
  • Successfully synchronized writes ('sent') are automatically pruned from the outbox after 24 hours.
  • Failed/dead-lettered outbox writes ('failed') are automatically deleted after 7 days, and the dead-letter queue is capped at a maximum of 100 records to prevent database bloating.
• Diagnostic Controls: If you need to clear the local cache or outbox (for troubleshooting or privacy reasons), the plugin provides programmatic controls via the XMemoLocalCache class:
  • local_cache.clear_cache(): Safe to call at any time. Instantly clears all cached read queries.
  • local_cache.clear_outbox(): Instantly purges all queued write operations.

    [!CAUTION] Wiping the outbox will permanently delete any pending or held write operations that have not yet synchronized to the XMemo cloud.

Uninstall or disable

To disable XMemo without removing files:

hermes config set memory.provider ""

To remove the plugin entirely:

rm -rf "${HERMES_HOME:-$HOME/.hermes}/plugins/xmemo"

Learn more

• xmemo.dev — XMemo home
• XMemo agent discovery
• Hermes XMemo config
• XMemo hosted MCP fallback
• Hermes Agent docs: Memory Providers

License

MIT