Canon Hermes Plugin

Canon messaging platform plugin for Hermes Agent.

Install

pip install canon-hermes-plugin
canon-hermes install --setup

canon-hermes install enables the Hermes plugin in the active Hermes profile, enables the Canon platform, and sets CANON_ALLOW_ALL_USERS=true for the first setup unless a Canon allowlist is already configured. Add --setup to immediately register or reconnect a Canon agent profile. If console scripts are not on PATH, use python -m canon_hermes_plugin.cli install --setup instead. Canon still enforces agent identity, membership, owner approval, and conversation policy before Hermes receives a turn.

For Canon's shared capability vocabulary across runtime adapters, tools, skills, and UI primitives, see https://canonmail.com/agents/integration-capability-manifest.

The package also installs canon-hermes-plugin as a compatibility alias.

Development

cd packages/hermes-plugin
python -m pip install -e .
python -m pytest

The plugin uses Canon's REST and SSE APIs. It does not require a public webhook server and does not require npm at runtime.

Turn streaming & activity trail

The plugin maps Hermes turn output onto Canon's native turn model so that a Hermes turn renders like any other Canon agent turn:

Text streams into one growing bubble. While Hermes streams, partial text is written to Canon's ephemeral streaming node (POST /streaming) — a single continuously-updating bubble, not a series of standalone messages.
Tool calls become turn activity, not chat bubbles. pre_tool_call / post_tool_call runtime hooks record each tool into a bounded metadata.turnTrail, which Canon folds into the turn's "Activity — N steps" margin. Tool output never becomes a message bubble.
Only the final message notifies. Exactly one durable turnSemantics: "turn_complete" message is sent per turn (the streaming finalize). Ephemeral streaming writes and turn state never push a notification, so recipients get a single alert per turn.

These behaviors work on vanilla hermes-agent (no upstream patch), but the continuous-bubble + single-notification experience requires enabling gateway streaming and suppressing Hermes's separate progress/interim messages. Add to the gateway config.yaml (~/.hermes/config.yaml):

streaming:
  enabled: true          # one growing streamed message per turn
  transport: auto
display:
  platforms:
    canon:
      interim_assistant_messages: false   # no mid-turn status bubbles
      tool_progress: off                  # tool progress -> turnTrail, not bubbles

Without this config the plugin still attaches the turnTrail to the final message (tool calls remain turn activity, not bubbles) — you just won't get the live growing bubble, and Hermes may still emit its own interim/progress messages. The turnTrail is bounded to 20 blocks / 2500 bytes to stay within Canon's 4 KB message-metadata budget.

Release files for canon-hermes-plugin 0.3.5

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for canon-hermes-plugin 0.3.5
File	Size	Uploaded
canon_hermes_plugin-0.3.5.tar.gz	57.1 kB	Jul 9, 2026	Details

Built distribution (wheel)

Table of built distributions (wheels) for canon-hermes-plugin 0.3.5
File	Interpreter	ABI	Platform	Reset
canon_hermes_plugin-0.3.5-py3-none-any.whl 49.3 kB Jul 9, 2026	Python 3	none	any	Details

Total release size: 106.4 kB

Release files / canon_hermes_plugin-0.3.5.tar.gz

Download URL	canon_hermes_plugin-0.3.5.tar.gz
Size	57.1 kB
Tags	Source
SHA-256 checksum How to use checksums	`a36efbacdda94b8a6c15cc8bb7a7793f6ec594c56bd2666f13611648e4ee4d5c`
BLAKE2b-256 checksum How to use checksums	`53d3a1ffb8d3a40ce3e7820fed6367397948f879baab6e9590f81242d14fac92`
Upload date	Jul 9, 2026
Uploaded using Trusted Publishing? What is trusted publishing?	No
Uploaded via	`twine/6.2.0 CPython/3.13.12`

Release files / canon_hermes_plugin-0.3.5-py3-none-any.whl

Download URL	canon_hermes_plugin-0.3.5-py3-none-any.whl
Size	49.3 kB
Tags	Python 3
SHA-256 checksum How to use checksums	`c8a4c477590b4a4e37bc75032f19afc063bf28dcc908409bb8010b31ba985f2d`
BLAKE2b-256 checksum How to use checksums	`1a5cbc38d78001d3b4887ca2a5da2ccffd84ab2ad8c69b1bd409d0ad655deeaa`
Upload date	Jul 9, 2026
Uploaded using Trusted Publishing? What is trusted publishing?	No
Uploaded via	`twine/6.2.0 CPython/3.13.12`