Hermes v0.15 Shrinks Core by 76%, Adds Multi-Agent Swarm

Hermes Agent v0.15 shipped May 28 as the "Velocity Release." Three days and two patch releases later, NousResearch teased something bigger.

The teaser pulled 974 likes, 59 retweets, and 232K impressions off zero details. No repo link. No specs. No timeline.

The v0.15 numbers: 1,302 commits, 747 merged PRs, 1,746 files changed, 282,712 insertions against 36,699 deletions, 560+ issues closed (15 P0, 65 P1), and 321 community contributors since v0.14.

The Refactor

The agent conversation loop lived in a single file: run_agent.py, 16,083 lines. It is now 3,821 lines spread across 14 modules under agent/. Every extraction keeps a thin forwarder on AIAgent. Behavior is unchanged. Plugin authors can grep the codebase. The file that took 90 seconds to load opens in a blink.

Multi-Agent Kanban

Kanban grew across 104 PRs into a multi-agent platform. hermes kanban swarm creates a full topology in one command: root decomposer, parallel workers, gated verifier, gated synthesizer, shared blackboard. Tasks support per-task model overrides (cheap models for boilerplate, expensive ones for hard sub-tasks), board-level workdirs, per-task worktree paths, scheduled start times, configurable claim TTL, retry fingerprinting, and stale-task detection.

Workers report through /workers/active, /runs/{id}, and /inspect endpoints for runtime observability.

Speed

Session search is 4,500x faster and now free. Cold start dropped another second: hermes --version beats Codex CLI head-to-head. Per-conversation function calls dropped 47%. Promptware defense landed against Brainworm-class attacks.

The Hotfixes

v0.15.1 shipped same-day to fix the dashboard 401 reload loop. In loopback mode (Docker, hosted Hermes), the dashboard's identity probe returned 401 by design, but the stale-token reload guard treated every 401 as a rotated session token. Firefox saw a "Navigated to /sessions" storm; Chrome hit a React re-render storm. Also included: kanban worker SIGTERM, model picker unification, and the full 19,932-entry skills catalog.

v0.15.2 followed the next day with further stabilizations.

Community Building on Top

Marchel's post on running Hermes as a cron agent with skill composition hit 175 impressions.

Ajith built a Hermes + PostHog pipeline that runs every morning at 9:30 AM, analyzing the previous day's analytics and reporting funnel leaks, user failures, rage clicks, and paying-user behavior. [^1]

Xaitoshi showed ClashHermes, an agentic gaming and trading agent on the Hermes stack. Kaylee highlighted Tool Search: "Loading only the relevant tools is the right tradeoff: lower token drag, less context noise, better agent decisions." [^2]

The Next Thing

v0.15 already delivered a 76% core reduction and multi-agent swarms. If this was the setup, the main event has not landed yet. The teaser is one line, no link, no commit. Agent developers are watching.

[^1]: Ajith. "Built a simple AI workflow Hermes + PostHog." X. May 31, 2026. [^2]: Kaylee. "Tool Search is the part that makes Hermes feel like an actual runtime." X. May 31, 2026.