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Hermes Agent Hermes Agent v0.21.4 (v2026.9.21)

2026-09-21 · official notes

Summary

• Hermes Agent v0.21.4 (v2026.9.21)
• Release Date: September 21, 2026
• Patch release. This tag rolls up the ~1,800 PRs merged since v0.21.3 into a stable tagged release for downstream consumers (Docker images, Hermes Cloud, hosted deployments). Full curated notes for thi

Full notes

# Hermes Agent v0.21.4 (v2026.9.21)

**Release Date:** September 21, 2026

> Patch release. This tag rolls up the ~1,800 PRs merged since v0.21.3 into a stable tagged release for downstream consumers (Docker images, Hermes Cloud, hosted deployments). Full curated notes for this window are deferred to v0.22.0.

## About this release

Measured at commit `4b8a8134009a8727a289bcabeb0019fedd353128`, the window since v0.21.3 contains **5,071 non-merge commits** across **5,169 changed files** (+312,961 / −62,855), **1,812 merged PRs** and **2,116 closed issues**.

Also in the window, undocumented here on purpose: a host-wide gateway singleton lock with a rendezvous record, and Desktop attaching to the running host backend instead of spawning a second one; one backend-owned connector operation with a setup card on Desktop, TUI and CLI; `--format stream-json` structured JSONL output for the CLI; `skills.auto_load` pinning skills into every new session's prompt; a Desktop chat/UI font picker, one-click local engine updates, and plugin uninstall from the Plugins hub; a `decline` unauthorized-DM behavior for the gateway; a configurable MCP discovery connect cap (`mcp.discovery_concurrency`); `session_search` after/before bounds plus OR-relaxed recall retry; `hermes sessions set-journal-mode`; LTX 2.5 and Kling O3 in the video catalogs; a website page for every catalog plugin and author, with pinned-commit READMEs and added/updated sorting; a dozen new community plugins in the catalog (tailscale, ssh, shodan, terminal, rss, resetwatch, done-bell, kiwi, cognee, Octen); and a large run of profile/multiplex isolation, cron, kanban, Desktop and state.db fixes.

**Full curated release notes for this window ship with v0.22.0**, which will document everything from v0.21.0 onward — highlights, feature areas, and complete contributor credits. Nothing in this window is skipped.

## Updating

- `hermes update` (git installs), or re-run the installer one-liner.
- Docker / Hermes Cloud: images build from this tag (`nousresearch/hermes-agent:v2026.9.21`).

**Full changelog:** https://github.com/NousResearch/hermes-agent/compare/v2026.9.14...v2026.9.21