---
sidebar_position: 7
title: "Sessions"
description: "Session persistence, resume, search, management, and per-platform session tracking"
---

import useBaseUrl from '@docusaurus/useBaseUrl';

# Sessions

Hermes Agent automatically saves every conversation as a session. Sessions enable conversation resume, cross-session search, and full conversation history management.

## How Sessions Work

Every conversation — whether from the CLI, Telegram, Discord, Slack, WhatsApp, Signal, Matrix, Teams, or any other messaging platform — is stored as a session with full message history. Sessions are tracked in:

1. **SQLite database** (`~/.hermes/state.db`) — structured session metadata with FTS5 full-text search, plus full message history

The SQLite database stores:
- Session ID, source platform, user ID
- **Session title** (unique, human-readable name)
- Model name and configuration
- System prompt snapshot
- Full message history (role, content, tool calls, tool results)
- Token counts (input/output)
- Timestamps (started_at, ended_at)
- Parent session ID (for compression-triggered session splitting)

### What Counts Toward Context

Hermes stores session history so it can resume conversations, but it does not
keep re-sending every byte it has ever handled. On each turn, the model sees
the selected system prompt, the current conversation window, and any content
Hermes explicitly injects for that turn.

Media attachments are handled as turn-scoped inputs:

- Images may be attached natively to the next model call, or pre-analyzed into
  a text description when the active model does not support native vision.
- Audio is transcribed into text when speech-to-text is configured.
- Text documents can have their extracted text included; other document types
  are usually represented by a saved local path and a short note.
- Attachment paths and extracted/derived text can appear in the transcript, but
  the raw image, audio, or binary file bytes are not repeatedly copied into
  future prompts.

For example, if a user sends an image and asks Hermes to make a meme from it,
Hermes may inspect that image once with vision and run an image-processing
script. Future turns do not automatically carry the original JPEG in context.
They carry only whatever was written into the conversation, such as the user's
request, a short image description, a local cache path, or the final assistant
response.

The most common cause of context growth is not the media file itself. It is
verbose text: pasted transcripts, full logs, large tool outputs, long diffs,
repeated status reports, and detailed proof dumps. Prefer summaries, file
paths, focused excerpts, and tool-backed lookups over copying large artifacts
into chat.

:::tip
Use `/compress` when a session gets long, `/new` for a fresh thread, and
`hermes sessions prune` only when you want to delete old ended sessions from
storage. If `state.db` has simply grown large, start with the non-destructive
option first: `hermes sessions optimize` merges FTS5 index segments and
VACUUMs the database without touching any session data. Compression reduces the active context; it is not a privacy delete.
Pass a name to `/new` (e.g. `/new payments-refactor`) to set the new session's
initial title up front — useful for finding it later with `/resume <name>` or
in the `/sessions` picker.
:::

### Session Sources

Each session is tagged with its source platform:

| Source | Description |
|--------|-------------|
| `cli` | Interactive CLI (`hermes` or `hermes chat`) |
| `telegram` | Telegram messenger |
| `discord` | Discord server/DM |
| `slack` | Slack workspace |
| `whatsapp` | WhatsApp messenger |
| `signal` | Signal messenger |
| `matrix` | Matrix rooms and DMs |
| `mattermost` | Mattermost channels |
| `email` | Email (IMAP/SMTP) |
| `sms` | SMS via Twilio |
| `dingtalk` | DingTalk messenger |
| `feishu` | Feishu/Lark messenger |
| `wecom` | WeCom (WeChat Work) |
| `weixin` | Weixin (personal WeChat) |
| `bluebubbles` | Apple iMessage via BlueBubbles macOS server |
| `qqbot` | QQ Bot (Tencent QQ) via Official API v2 |
| `homeassistant` | Home Assistant conversation |
| `webhook` | Incoming webhooks |
| `api-server` | API server requests |
| `acp` | ACP editor integration |
| `cron` | Scheduled cron jobs |
| `batch` | Batch processing runs |

## CLI Session Resume

Resume previous conversations from the CLI using `--continue` or `--resume`:

### Continue Last Session

```bash
# Resume the most recent CLI session
hermes --continue
hermes -c

# Or with the chat subcommand
hermes chat --continue
hermes chat -c
```

This looks up the most recent `cli` session from the SQLite database and loads its full conversation history.

### Resume by Name

If you've given a session a title (see [Session Naming](#session-naming) below), you can resume it by name:

```bash
# Resume a named session
hermes -c "my project"

# If there are lineage variants (my project, my project #2, my project #3),
# this automatically resumes the most recent one
hermes -c "my project"   # → resumes "my project #3"
```

### Resume Specific Session

```bash
# Resume a specific session by ID
hermes --resume 20250305_091523_a1b2c3d4
hermes -r 20250305_091523_a1b2c3d4

# Resume by title
hermes --resume "refactoring auth"

# Or with the chat subcommand
hermes chat --resume 20250305_091523_a1b2c3d4
```

Session IDs are shown when you exit a CLI session, and can be found with `hermes sessions list`.

### Resume Restores the Working Directory

Resuming a CLI session also `cd`s back into the session's recorded working directory (its git repo root or project dir), so the conversation picks up in the workspace it belonged to. If you'd rather stay where you are, pass `--no-restore-cwd`:

```bash
hermes --resume 20250305_091523_a1b2c3 --no-restore-cwd
```

A `↪ restored workspace dir: …` line confirms the switch. Restore failures never break the resume itself.

### Filtering Sessions by Workspace

`hermes sessions list` accepts `--workspace <needle>` to show only sessions whose workspace key (git repo root, else cwd) matches — by path substring or exact directory basename:

```bash
hermes sessions list --workspace my-project
hermes sessions list --workspace ~/code/hermes-agent
```

### Conversation Recap on Resume

When you resume a session, Hermes displays a compact recap of the previous conversation in a styled panel before the input prompt:

<img className="docs-terminal-figure" src={useBaseUrl('/img/docs/session-recap.svg')} alt="Stylized preview of the Previous Conversation recap panel shown when resuming a Hermes session." />
<p className="docs-figure-caption">Resume mode shows a compact recap panel with recent user and assistant turns before returning you to the live prompt.</p>

The recap:
- Shows **user messages** (gold `●`) and **assistant responses** (green `◆`)
- **Truncates** long messages (300 chars for user, 200 chars / 3 lines for assistant)
- **Collapses tool calls** to a count with tool names (e.g., `[3 tool calls: terminal, web_search]`)
- **Hides** system messages, tool results, and internal reasoning
- **Caps** at the last 10 exchanges with a "... N earlier messages ..." indicator
- Uses **dim styling** to distinguish from the active conversation

To disable the recap and keep the minimal one-liner behavior, set in `~/.hermes/config.yaml`:

```yaml
display:
  resume_display: minimal   # default: full
```

:::tip
Session IDs follow the format `YYYYMMDD_HHMMSS_<hex>` — CLI/TUI sessions use a 6-char hex suffix (e.g. `20250305_091523_a1b2c3`), gateway sessions use an 8-char suffix (e.g. `20250305_091523_a1b2c3d4`). You can resume by ID (full or unique prefix) or by title — both work with `-c` and `-r`.
:::

## Cross-Platform Handoff

Use `/handoff <platform>` from a CLI session to transfer the live conversation to a messaging platform's home channel. The agent picks up exactly where the CLI left off — same session id, full role-aware transcript, tool calls and all.

```bash
# Inside a CLI session
/handoff telegram
```

What happens:

1. The CLI validates that `<platform>` is enabled and has a home channel set (run `/sethome` from the destination chat once to configure it).
2. The CLI marks the session pending and **block-polls the gateway**. It refuses if the agent is mid-turn — wait for the current response to finish first.
3. The gateway watcher claims the handoff and asks the destination adapter for a fresh thread:
   - **Telegram** — opens a new forum topic (DM topics if Bot API 9.4+ Topics mode is enabled in the chat, or a forum supergroup topic).
   - **Discord** — creates a 1440-min auto-archive thread under the home text channel.
   - **Slack** — posts a seed message and uses its `ts` as the thread anchor.
   - **WhatsApp / Signal / Matrix / SMS** — no native threads, falls back to the home channel directly.
4. The gateway re-binds the destination key to your existing CLI session id, then forges a synthetic user turn asking the agent to confirm and summarize. The reply lands in the new thread.
5. When the gateway acknowledges success, the CLI prints a `/resume` hint and exits cleanly:

   ```
   ↻ Handoff complete. The session is now active on telegram.
     Resume it on this CLI later with: /resume my-session-title
   ```

6. From that point, the conversation lives on the platform. Reply in the new thread — anyone authorized in that channel shares the same session, and any later real user message in the thread joins seamlessly because thread sessions key without `user_id`.

**Resume back to CLI:** when you want to come back to a desktop, just run `/resume <title>` (or `hermes -r "<title>"` from the shell) and pick up where the platform left off.

**Failure modes:**
- No home channel configured → CLI refuses with a `/sethome` hint.
- Platform not enabled / gateway not running → CLI times out at 60s with a clear message and your CLI session stays intact.
- Thread creation fails (permissions, topics-mode off) → falls back to the home channel directly and still completes; no thread isolation but the handoff itself works.
- `adapter.send` fails (rate limit, transient API error) → handoff marked failed with the reason; the row clears so you can retry.

**Limitation worth knowing:** for non-thread-capable platforms with multi-user group home channels, the synthetic turn keys as a DM-style session. This works for self-DM home channels (the typical setup) but isn't ideal for genuinely shared group chats. Threading covers Telegram / Discord / Slack — by far the common case — so most setups never hit this.

## Session Naming

Give sessions human-readable titles so you can find and resume them easily.

### Auto-Generated Titles

Hermes automatically generates a short descriptive title (3–7 words) for each session after the first exchange. This runs in a background thread using a fast auxiliary model, so it adds no latency. You'll see auto-generated titles when browsing sessions with `hermes sessions list` or `hermes sessions browse`.

Auto-titling only fires once per session and is skipped if you've already set a title manually.

### Setting a Title Manually

Use the `/title` slash command inside any chat session (CLI or gateway):

```
/title my research project
```

The title is applied immediately. If the session hasn't been created in the database yet (e.g., you run `/title` before sending your first message), it's queued and applied once the session starts.

You can also rename existing sessions from the command line:

```bash
hermes sessions rename 20250305_091523_a1b2c3d4 "refactoring auth module"
```

### Title Rules

- **Unique** — no two sessions can share the same title
- **Max 100 characters** — keeps listing output clean
- **Sanitized** — control characters, zero-width chars, and RTL overrides are stripped automatically
- **Normal Unicode is fine** — emoji, CJK, accented characters all work

### Auto-Lineage on Compression

When a session's context is compressed (manually via `/compress` or automatically), Hermes creates a new continuation session. If the original had a title, the new session automatically gets a numbered title:

```
"my project" → "my project #2" → "my project #3"
```

When you resume by name (`hermes -c "my project"`), it automatically picks the most recent session in the lineage.

### /title in Messaging Platforms

The `/title` command works in all gateway platforms (Telegram, Discord, Slack, WhatsApp):

- `/title My Research` — set the session title
- `/title` — show the current title

## Session Management Commands

Hermes provides a full set of session management commands via `hermes sessions`:

### List Sessions

```bash
# List recent sessions (default: last 20)
hermes sessions list

# Filter by platform
hermes sessions list --source telegram

# Show more sessions
hermes sessions list --limit 50
```

When sessions have titles, the output shows titles, previews, and relative timestamps:

```
Title                  Preview                                  Last Active   ID
────────────────────────────────────────────────────────────────────────────────────────────────
refactoring auth       Help me refactor the auth module please   2h ago        20250305_091523_a
my project #3          Can you check the test failures?          yesterday     20250304_143022_e
—                      What's the weather in Las Vegas?          3d ago        20250303_101500_f
```

When no sessions have titles, a simpler format is used:

```
Preview                                            Last Active   Src    ID
──────────────────────────────────────────────────────────────────────────────────────
Help me refactor the auth module please             2h ago        cli    20250305_091523_a
What's the weather in Las Vegas?                    3d ago        tele   20250303_101500_f
```

### Export Sessions

`hermes sessions export` is one surface for every export format, selected with `--format`:

| Format | Output | Use it for |
|--------|--------|------------|
| `jsonl` (default) | one JSON object per session | backups, machine round-trip |
| `md` / `qmd` | one Markdown/Quarto file per session + manifest | readable archives, notes |
| `html` | single self-contained page (sidebar for multi-session) | sharing, browsing |
| `trace` | Claude Code JSONL | HF Agent Trace Viewer, `--upload` |

Plus `--only user-prompts` for a prompts-only view (jsonl or md).

All formats share the same selection knobs: `--session-id` for one session, or the full `prune`/`archive` filter set for bulk — `--older-than` / `--newer-than` / `--before` / `--after` (durations like `5h`/`2d`/`1w`, bare days, or ISO timestamps), `--source`, `--title`, `--model`, `--provider`, `--cwd`, `--min/--max-messages`, `--min/--max-tokens`, `--min/--max-cost`, `--min/--max-tool-calls`, `--user`, `--chat-id`, `--chat-type`, `--branch`, `--end-reason`. `--dry-run` previews the match set without writing. `--redact` scrubs secrets (API keys, tokens, credentials) from exported content on any format — recommended for anything you plan to share. Note: bulk filters match *ended* sessions; unfiltered `export` dumps everything, including active ones.

#### JSONL (default)

```bash
# Export all sessions to a JSONL file
hermes sessions export backup.jsonl

# Export sessions from a specific platform
hermes sessions export telegram-history.jsonl --source telegram

# Export a single session
hermes sessions export session.jsonl --session-id 20250305_091523_a1b2c3d4

# Redact API keys/tokens/credentials from the exported content
hermes sessions export backup.jsonl --redact
```

Exported files contain one JSON object per line with full session metadata and all messages.

#### HTML

`--format html` writes a single self-contained HTML file — no remote dependencies — with styled message bubbles, collapsible tool output, and (for multi-session exports) a sidebar to switch between sessions:

```bash
# One session as a standalone HTML page
hermes sessions export --format html --session-id 20250305_091523_a1b2c3d4 transcript.html

# All Telegram sessions from the last week in one file, secrets redacted
hermes sessions export --format html --newer-than 1w --source telegram --redact archive.html
```

#### Prompts Only

`--only user-prompts` exports just the prompts you wrote — no assistant replies, tool output, or system context. Useful for building prompt libraries or reviewing what you asked:

```bash
# One JSONL record per prompt (session id, index, timestamp, text)
hermes sessions export prompts.jsonl --session-id 20250305_091523_a1b2c3d4 --only user-prompts

# Markdown, straight to stdout
hermes sessions export - --session-id 20250305_091523_a1b2c3d4 --only user-prompts --format md
```

Works with `--format jsonl` (default) or `md`, honors the same filters for bulk export, and combines with `--redact`.

#### Traces (HF Agent Trace Viewer)

`--format trace` emits Claude Code JSONL — the transcript shape the Hugging Face Hub auto-detects for its [Agent Trace Viewer](https://huggingface.co/docs/hub/agent-traces). Write it locally, or add `--upload` to push it to your own private `hermes-traces` dataset (reads `HF_TOKEN`):

```bash
# Trace of the most recent session, to stdout
hermes sessions export --format trace

# One session to a local trace file
hermes sessions export --format trace --session-id 20250305_091523_a1b2c3d4 trace.jsonl

# Upload straight to your private HF traces dataset
hermes sessions export --format trace --session-id 20250305_091523_a1b2c3d4 --upload
```

Trace exports are secret-redacted by default (they're meant to leave the machine); `--no-redact` opts out after manual review. `--upload` is private unless `--public`. Bulk trace export with filters writes one `<id>.trace.jsonl` per session.

#### Markdown / QMD

Pass `--format md` or `--format qmd` when you want a readable, file-based archive before hiding or deleting old sessions. Markdown/QMD exports write one file per session into a directory (default: `~/.hermes/session-exports`).

```bash
# Export one session to Markdown
hermes sessions export --format md --session-id 20250305_091523_a1b2c3d4

# Export a compression lineage as one logical document
hermes sessions export --format md --session-id 20250305_091523_a1b2c3d4 --lineage logical

# Preview ended sessions older than 90 days without writing files
hermes sessions export --format md --older-than 90 --dry-run

# Export ended Telegram sessions older than 2 weeks to QMD files
hermes sessions export --format qmd --older-than 2w --source telegram

# Export long Claude sessions, secrets redacted
hermes sessions export --format md --model sonnet --min-messages 50 --redact

# Only after verification, export and delete one explicitly named session
hermes sessions export --format md --session-id 20250305_091523_a1b2c3d4 --delete-after-verified --yes
```

Markdown/QMD export writes one `.md` or `.qmd` file per exported session plus a `manifest.jsonl` with the file path, message count, lineage ids, and SHA-256. Bulk export requires at least one filter; a bare bulk export is refused. `--delete-after-verified` is intentionally limited to `--session-id` and requires `--yes`. Because deleting a parent session also removes its delegate/subagent sessions, this mode exports and verifies each delegate in a separate file before deleting anything. If the delegate set changes during export, deletion is refused. `--redact` scrubs secrets (API keys, tokens, credentials) from message content and tool output before writing — recommended for any export you plan to share.

### Delete a Session

```bash
# Delete a specific session (with confirmation)
hermes sessions delete 20250305_091523_a1b2c3d4

# Delete without confirmation
hermes sessions delete 20250305_091523_a1b2c3d4 --yes
```

### Rename a Session

```bash
# Set or change a session's title
hermes sessions rename 20250305_091523_a1b2c3d4 "debugging auth flow"

# Multi-word titles don't need quotes in the CLI
hermes sessions rename 20250305_091523_a1b2c3d4 debugging auth flow
```

If the title is already in use by another session, an error is shown.

### Prune Old Sessions

```bash
# Delete ended sessions inactive for 90 days (default)
hermes sessions prune

# Custom age threshold — bare numbers are days
hermes sessions prune --older-than 30

# Durations work too: 5h, 30m, 2d, 1w
hermes sessions prune --older-than 12h

# Delete only a specific time window (e.g. a batch of test sessions
# created in the last 5 hours)
hermes sessions prune --newer-than 5h

# Explicit window with absolute timestamps
hermes sessions prune --after "2026-07-05 09:00" --before "2026-07-05 14:30"

# Only prune sessions from a specific platform (all ages — any filter
# disables the implicit 90-day default)
hermes sessions prune --source telegram
hermes sessions prune --source cron --older-than 60   # add a time flag to narrow

# More filters — all AND together
hermes sessions prune --newer-than 5h --title "smoke test"   # title substring
hermes sessions prune --older-than 30 --max-messages 3        # tiny sessions
hermes sessions prune --cwd ~/scratch --end-reason done       # by cwd / end reason
hermes sessions prune --model gpt-5 --older-than 1w           # by model (substring)
hermes sessions prune --provider openrouter --older-than 60   # by billing provider
hermes sessions prune --branch feature/old-experiment         # by git branch
hermes sessions prune --user 12345678 --chat-type group       # by messaging origin
hermes sessions prune --max-tokens 500 --older-than 7         # by token usage
hermes sessions prune --max-cost 0.01 --max-tool-calls 0      # cheap, tool-less runs

# Preview what would be deleted, without deleting anything
hermes sessions prune --newer-than 5h --dry-run

# Skip confirmation
hermes sessions prune --older-than 30 --yes
```

Time values (`--older-than`, `--newer-than`, `--before`, `--after`) accept a
duration (`5h`, `30m`, `2d`, `1w`), a bare number of days, or an ISO
timestamp (`2026-07-05`, `2026-07-05 14:30`). `--older-than`/`--before` set
the upper bound; `--newer-than`/`--after` set the lower bound. The
`--older-than`/`--newer-than` pair uses latest message activity (falling back
to session start for empty sessions); `--before`/`--after` explicitly uses
session start time. Combine either pair for a window.

Attribute filters: `--source` (platform, exact), `--title` / `--model` /
`--branch` (case-insensitive substring), `--provider` (billing provider,
exact), `--end-reason`, `--user`, `--chat-id`, `--chat-type` (exact),
`--cwd` (path prefix), plus numeric bounds `--min/--max-messages`,
`--min/--max-tokens` (input+output), `--min/--max-cost` (USD, actual falling
back to estimated), and `--min/--max-tool-calls`. Using any filter disables
the implicit 90-day default, so `hermes sessions prune --source cron` or
`--model gpt-4o` matches all ages — add a time flag to narrow it. Only a
completely bare `hermes sessions prune` keeps the 90-day cutoff. Every
non-`--yes` run shows the match count plus the oldest and newest matching
session before asking for confirmation.

Archived sessions are skipped by default; pass `--include-archived` to
delete them too.

:::info
Pruning only deletes **ended** sessions (sessions that have been explicitly ended or auto-reset). Active sessions are never pruned.
:::

### Bulk-Archive Sessions

If you want sessions out of your listings without deleting anything,
`hermes sessions archive` takes the same filters as `prune` but soft-hides
matching sessions instead (sets the same archived flag as archiving a single
session from the Desktop/Dashboard UI — messages and search stay intact):

```bash
# Archive everything from the last 5 hours (e.g. 75 CI smoke-test sessions)
hermes sessions archive --newer-than 5h

# Archive by title substring, preview first
hermes sessions archive --title "dry run" --dry-run
hermes sessions archive --title "dry run" --yes
```

At least one filter is required — a bare `hermes sessions archive` refuses to
archive your entire history. Archived sessions are hidden from
`hermes sessions list` and `/resume` but remain in the database and can be
unarchived from the Desktop/Dashboard session list.

### Session Statistics

```bash
hermes sessions stats
```

Output:

```
Total sessions: 142
Total messages: 3847
  cli: 89 sessions
  telegram: 38 sessions
  discord: 15 sessions
Database size: 12.4 MB
```

For deeper analytics — token usage, cost estimates, tool breakdown, and activity patterns — use [`hermes insights`](/reference/cli-commands#hermes-insights).

## Session Search Tool

The agent has a built-in `session_search` tool that performs full-text search across all past conversations using SQLite's FTS5 engine — and lets the agent scroll through any session it finds. No LLM calls, no summarization, no truncation. Every shape returns actual messages from the DB.

### Three calling shapes

The tool infers what you want from which arguments you set. There's no `mode` parameter.

**1. Discovery — pass `query`:**

```python
session_search(query="auth refactor", limit=3)
```

Runs FTS5, dedupes hits by session lineage, returns the top N sessions. Each result carries:

- `session_id`, `title`, `when`, `source`
- `snippet` — FTS5-highlighted match excerpt
- `bookend_start` — first 3 user+assistant messages of the session (the goal/kickoff)
- `messages` — ±5 messages around the FTS5 match, with the anchor message flagged (the hit in context)
- `bookend_end` — last 3 user+assistant messages of the session (the resolution/decisions)
- `match_message_id`, `messages_before`, `messages_after`

Bookends + window together reconstruct goal → match → resolution without paying for the whole transcript. Typical wall time: 15–50ms on a real session DB.

**2. Scroll — pass `session_id` + `around_message_id`:**

```python
session_search(session_id="20260510_174648_805cc2", around_message_id=590803, window=10)
```

Returns a window of ±`window` messages centered on the anchor. No FTS5, no bookends — just the slice. Use after a discovery call when you need more context than the ±5 default window.

- To scroll **forward**: pass `messages[-1].id` back as `around_message_id`
- To scroll **backward**: pass `messages[0].id` back as `around_message_id`
- The boundary message appears in both windows as an orientation marker
- When `messages_before` or `messages_after` is less than `window`, you're at the start or end of the session

Typical wall time: 1–2ms per scroll call.

**3. Browse — no args:**

```python
session_search()
```

Returns recent sessions chronologically (titles, previews, timestamps). Useful when the user asks "what was I working on" without naming a topic.

### FTS5 query syntax

The keyword mode supports standard FTS5 query syntax:

- Simple keywords: `docker deployment` (FTS5 defaults to AND)
- Phrases: `"exact phrase"`
- Boolean: `docker OR kubernetes`, `python NOT java`
- Prefix: `deploy*`

### Optional parameters

- `sort` — `newest` or `oldest`, on top of FTS5 ranking. Omit for relevance-only ordering (the default; suitable for exploratory recall). Use `newest` for "where did we leave X" questions, `oldest` for "how did X start" questions.
- `role_filter` — comma-separated roles to include. Discovery defaults to `user,assistant` (tool output is usually noise). Pass `user,assistant,tool` to include tool output (debugging tool behaviour) or `tool` to search tool output only.

### When It's Used

The agent is prompted to use session search automatically:

> *"When the user references something from a past conversation or you suspect relevant prior context exists, use session_search to recall it before asking them to repeat themselves."*

Typical triggers: "we did this before", "remember when", "last time", "as I mentioned", or any reference to a project/person/concept that isn't in the current window.

## Per-Platform Session Tracking

### Gateway Sessions

On messaging platforms, sessions are keyed by a deterministic session key built from the message source:

| Chat Type | Default Key Format | Behavior |
|-----------|--------------------|----------|
| Telegram DM | `agent:main:telegram:dm:<chat_id>` | One session per DM chat |
| Discord DM | `agent:main:discord:dm:<chat_id>` | One session per DM chat |
| WhatsApp DM | `agent:main:whatsapp:dm:<canonical_identifier>` | One session per DM user (LID/phone aliases collapse to one identity when mapping exists) |
| Group chat | `agent:main:<platform>:group:<chat_id>:<user_id>` | Per-user inside the group when the platform exposes a user ID |
| Group thread/topic | `agent:main:<platform>:group:<chat_id>:<thread_id>` | Shared session for all thread participants (default). Per-user with `thread_sessions_per_user: true`. |
| Channel | `agent:main:<platform>:channel:<chat_id>:<user_id>` | Per-user inside the channel when the platform exposes a user ID |

When Hermes cannot get a participant identifier for a shared chat, it falls back to one shared session for that room.

### Shared vs Isolated Group Sessions

By default, Hermes uses `group_sessions_per_user: true` in `config.yaml`. That means:

- Alice and Bob can both talk to Hermes in the same Discord channel without sharing transcript history
- one user's long tool-heavy task does not pollute another user's context window
- interrupt handling also stays per-user because the running-agent key matches the isolated session key

If you want one shared "room brain" instead, set:

```yaml
group_sessions_per_user: false
```

That reverts groups/channels to a single shared session per room, which preserves shared conversational context but also shares token costs, interrupt state, and context growth.

### Session Reset Policies

**By default gateway sessions never auto-reset** (`mode: none`). You can opt
in to automatic resets via the `session_reset` section in `config.yaml`:

- **none** — never auto-reset (default; context managed by `/reset` and compression)
- **idle** — reset after N minutes of inactivity
- **daily** — reset at a specific hour each day
- **both** — reset on whichever comes first (idle or daily)

Before a session is auto-reset, the agent is given a turn to save any important memories or skills from the conversation.

Sessions with **active background processes** are never auto-reset, regardless of policy.

## Storage Locations

| What | Path | Description |
|------|------|-------------|
| SQLite database | `~/.hermes/state.db` | All session metadata + messages with FTS5 |
| Gateway messages    | `~/.hermes/state.db`   | SQLite — canonical store for all session messages |
| Gateway routing index | `gateway_routing` table in `~/.hermes/state.db` | Maps session keys to active session IDs (origin metadata, expiry flags) |
| Legacy routing mirror | `~/.hermes/sessions/sessions.json` | Backward-compat mirror of the routing index, written when `gateway.write_sessions_json: true` (the default) |

The SQLite database uses WAL mode for concurrent readers and a single writer, which suits the gateway's multi-platform architecture well.

:::warning `sessions.json` is not the session list
The gateway routing index lives in the `gateway_routing` table inside
`state.db`; `~/.hermes/sessions/sessions.json` is a **legacy mirror** of it,
kept for backward compatibility (disable with
`gateway.write_sessions_json: false`). It maps messaging session keys
(`agent:main:<platform>:...`) to active session IDs.
It only ever contains gateway/messaging entries, so if you run a messaging
platform you'll see only those (e.g. `agent:main:whatsapp:dm:...`).

This is **expected** and does **not** mean your CLI sessions are missing.
`hermes sessions list`, `/sessions`, and the dashboard all read `state.db`,
which holds **every** session (CLI, TUI, and gateway). The `/save` snapshots
under `~/.hermes/sessions/saved/*.json` are convenience exports, not the index.

If CLI sessions genuinely don't appear in `hermes sessions list`, the cause is
`state.db` not receiving them — run `hermes sessions repair` and watch for a
`⚠ Session store unavailable` warning at CLI startup, which means SQLite
persistence failed for that run.
:::

:::note Legacy JSONL transcripts
Sessions created before state.db became canonical may have leftover
`*.jsonl` files in `~/.hermes/sessions/`. They are no longer written or
read by Hermes. Safe to delete after verifying the corresponding session
exists in state.db.
:::

### Database Schema

Key tables in `state.db`:

- **sessions** — session metadata (id, source, user_id, model, title, timestamps, token counts). Titles have a unique index (NULL titles allowed, only non-NULL must be unique).
- **messages** — full message history (role, content, tool_calls, tool_name, token_count)
- **messages_fts** — FTS5 virtual table for full-text search across message content

## Session Expiry and Cleanup

### Automatic Cleanup

- Gateway sessions auto-reset based on the configured reset policy
- Before reset, the agent saves memories and skills from the expiring session
- Opt-in auto-pruning: when `sessions.auto_prune` is `true`, ended sessions inactive for `sessions.retention_days` (default 90) are pruned at CLI/gateway startup
- After a prune that actually removed rows, `state.db` is `VACUUM`ed to reclaim disk space when at least `sessions.min_vacuum_interval_days` (default 30) have elapsed since the last successful `VACUUM` (SQLite does not shrink the file on plain DELETE)
- Pruning runs at most once per `sessions.min_interval_hours` (default 24); the last-run timestamp is tracked inside `state.db` itself so it's shared across every Hermes process in the same `HERMES_HOME`

Default is **off** — session history is valuable for `session_search` recall, and silently deleting it could surprise users. Enable in `~/.hermes/config.yaml`:

```yaml
sessions:
  auto_prune: true          # opt in — default is false
  retention_days: 90        # keep ended sessions active within this window
  vacuum_after_prune: true  # reclaim disk space after a pruning sweep
  min_vacuum_interval_days: 30 # don't rewrite the DB more often than this
  min_interval_hours: 24    # don't re-run the sweep more often than this
```

Active sessions are never auto-pruned, regardless of age. Ended sessions are
aged from their latest message, so a long-lived conversation used recently is
not deleted merely because it began before the retention window.

### Manual Cleanup

```bash
# Prune sessions older than 90 days
hermes sessions prune

# Delete a specific session
hermes sessions delete <session_id>

# Export before pruning (backup)
hermes sessions export backup.jsonl
hermes sessions prune --older-than 30 --yes
```

:::tip
The database grows slowly (typical: 10-15 MB for hundreds of sessions) and session history powers `session_search` recall across past conversations, so auto-prune ships disabled. Enable it if you're running a heavy gateway/cron workload where `state.db` is meaningfully affecting performance (observed failure mode: 384 MB state.db with ~1000 sessions slowing down FTS5 inserts and `/resume` listing). Use `hermes sessions prune` for one-off cleanup without turning on the automatic sweep.
:::
