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 0.3.3

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 0.3.3
File	Size	Uploaded
canon_hermes_plugin-0.3.3.tar.gz	54.1 kB	Jul 8, 2026	Details

Built distribution (wheel)

Table of built distributions (wheels) for canon-hermes-plugin 0.3.3
File	Interpreter	ABI	Platform	Reset
canon_hermes_plugin-0.3.3-py3-none-any.whl 46.8 kB Jul 8, 2026	Python 3	none	any	Details

Total release size: 100.9 kB

Release files / canon_hermes_plugin-0.3.3.tar.gz

Download URL	canon_hermes_plugin-0.3.3.tar.gz
Size	54.1 kB
Tags	Source
SHA-256 checksum How to use checksums	`993072cf7332b984ccbc766605d9884858cf771d0cd7e94f5eafceb3792cb2e8`
BLAKE2b-256 checksum How to use checksums	`4d671abe5a0daf363328537b75f6c7d5078a1a9b5f9f2f49b85791dad19dba72`
Upload date	Jul 8, 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-0.3.3-py3-none-any.whl

Download URL	canon_hermes_plugin-0.3.3-py3-none-any.whl
Size	46.8 kB
Tags	Python 3
SHA-256 checksum How to use checksums	`39da39ce886d2a9b2104baa3ac2651a5ed80355438e15f24cfb8034eeb5da5a2`
BLAKE2b-256 checksum How to use checksums	`7ac2717e60efccc533603f9644b78e41eced47df1ac32d6216b16a0cbc62f3ff`
Upload date	Jul 8, 2026
Uploaded using Trusted Publishing? What is trusted publishing?	No
Uploaded via	`twine/6.2.0 CPython/3.13.12`