Skip to content
HARNESS CLI

Hermes Agent Is Now a First-Class AIOS Client

Hermes Agent Is Now a First-Class AIOS Client

Hermes Agent (the open-source CLI AI agent by Nous Research) now joins Codex CLI, Claude Code, Gemini CLI, OpenCode, and Crush as the seventh first-class AIOS client in Harness CLI.

This isn't just a config entry. The core of this integration is an MCP bridge server — exposing AIOS's five most valuable capabilities as MCP tools that Hermes can call directly.

Why Hermes Agent needed this

Hermes already ships session_search, memory, delegate_task, skill_manage, and cronjob as built-in tools. But like every other AIOS client, it lacks systematic support in three areas:

  1. Strategic context recall — Hermes can search session history, but it can't trim by token budget with priority sorting. Long sessions flood the context window with low-value history.
  2. Environment health self-checks — Wrong MCP config, outdated Node version, broken skill directories — these silent problems drag down entire workflows, but Hermes has no automatic detection or repair.
  3. Large output compression — Browser screenshots, long shell output, and HTML dumps waste tokens when they go straight into the context window. Hermes has no interception layer.

The AIOS MCP bridge closes all three gaps.

The 5 MCP tools

scripts/aios-mcp-server.mjs is the new MCP bridge server. It exposes five tools:

aios_context_pack

Token-budget-aware context compression. Three strategies:

Strategy Behavior Use case
legacy Tail truncation Simple scenarios, no priority
balanced Priority-sorted pruning Daily use, keeps most important info
aggressive Only critical signals Harness/checkpoint mode, max compression
# Call from inside a Hermes session
aios_context_pack(query="auth bug fix history", token_budget=2000, strategy="balanced")

aios_doctor_suite

Full health check — MCP config, Node version, ContextDB status, skill directories, and client connectivity. Supports --fix for auto-repair.

aios_doctor_suite(workspace="/path/to/project", fix=true)

aios_intercept_compress

Large tool output compression. Three compression modes:

Mode Compression level Use case
tight Balanced Default
ultra Maximum Harness/checkpoints
precise Minimal Safety-critical operations
aios_intercept_compress(text="<raw browser output>", mode="tight", tool_name="page.screenshot")

aios_skill_validate

Validate Hermes/AIOS skill directory structure — checks SKILL.md frontmatter required fields (name, description, version, author), content completeness, and referenced file existence.

aios_skill_validate(skill_path="/path/to/.hermes/skills/my-skill")

aios_skill_install

Install skills from AIOS skill-sources into Hermes's .hermes/skills/ directory. Supports copy (portable) and link (local dev) install modes.

aios_skill_install(skill_name="context-pack", install_mode="copy")

Client registration details

Hermes is registered in CLIENT_DEFINITIONS with:

Property Value Notes
capabilities skills, native, harness, superpowers No team/agents yet
commandName hermes CLI command
runtimeClientId hermes-agent Runtime identifier
projectSkillRoot .hermes/skills Skill install directory
instructionFileName AGENTS.md Hermes auto-loads project root AGENTS.md
modelArgFlag --model Model selection flag
unattendedArgs empty Hermes has no --yolo mode

MCP config dual-scope:

Scope File Notes
Project .mcp.json Shared with Claude Code
Home config.yaml (under ~/.hermes/) Hermes YAML config

How to enable

Step 1: Make sure AIOS is installed

aios doctor

Step 2: Run Setup

aios          # TUI → Setup → select hermes

Or directly:

aios setup --client hermes

Step 3: Verify MCP bridge

aios doctor --fix
# Doctor auto-registers aios-mcp-server into Hermes MCP config

Step 4: Use in Hermes

Start Hermes in any project. The 5 AIOS MCP tools are automatically available:

hermes
# In conversation: @aios_context_pack query="..." token_budget=2000 strategy="balanced"

Differences from other clients

Feature Codex/Claude Hermes
Skills directory .codex/skills / .claude/skills .hermes/skills
Instruction file AGENTS.md / CLAUDE.md AGENTS.md (shared)
Unattended mode --yolo / --dangerously-skip-permissions None (uses delegate_task)
MCP config JSON / TOML JSON + YAML dual-scope
Team orchestration Supported Not yet (future extension)

What's next

  • Distill Hermes-native skills — Extract context-pack, hermes-doctor etc. from AIOS skill-sources into .hermes/skills/ format
  • Team orchestration extension — Hermes delegate_task already supports sub-agent dispatch; future integration with AIOS multi-client team orchestration
  • ACP sub-agent bridge — Hermes supports ACP (e.g. Copilot CLI); could merge with AIOS delegate_task for cross-client orchestration

Read the AIOS docs for the full guide, or check Agent Governance to see how AIOS keeps multi-client workflows safe.