Under gateway.multiplex_profiles (and the Desktop/dashboard backend serving named
profiles) os.environ holds the LAUNCH profile's .env. Five spawn sites built a
child's env from it while acting for another profile, so the child saw the
launch profile's HERMES_HOME (bot_relay, key_cmd), its credentials, HERMES_MODEL
and TERMINAL_* policy, and none of the served profile's own .env:
- tui_gateway/server.py _SlashWorker: pinned HERMES_HOME but kept the launch
base with tier-2 credentials + settings.
- tools/bot_relay.py delivery_env (relay RPC + --run-delivery): dict(os.environ).
- tools/browser_tool.py _build_browser_env: re-added BROWSERBASE/FIRECRAWL/
BROWSER_USE keys from os.environ after the scrub.
- plugins/platforms/a2a/adapter.py _forward_to_profile: {**os.environ}.
- agent/command_token_source.py _mint: key_cmd helper inherited os.environ.
tools.environments.local.served_profile_child_env is the one builder: pin the
target home, drop the launch profile's .env residue and bridged TERMINAL_*
(strip_launch_profile_env), and for children that legitimately run with the
profile's credentials (agent worker, token helper) overlay the target profile's
own secrets - what a standalone `hermes -p X` loads itself, never a sibling's.
The browser keeps the provider scrub and re-adds only its passthrough keys via
get_secret. Outside multiplex the env is unchanged.
Live proof from inside the child (launch A, served B, multiplex on): all five
children print HERMES_HOME == B, see B_MARKER=b from B's .env and do not see
A_MARKER; the browser child gets B's FIRECRAWL_API_KEY. On base every one leaked
A_MARKER and lacked B_MARKER; bot_relay and key_cmd also had A's HERMES_HOME.
A2A — Agent-to-Agent protocol for Hermes
Talk to other agents, and let other agents talk to you, over the open
A2A protocol v1.0. Works with any A2A-compliant
peer (another Hermes, LangChain, CrewAI, Google ADK, OpenClaw, …). Stdlib only —
no a2a-sdk dependency.
Enable
hermes gateway setup # pick A2A, or:
# ~/.hermes/config.yaml
gateway:
platforms:
a2a:
enabled: true
extra:
port: 9900
# peers you want to call (outbound):
a2a_agents:
researcher:
url: "http://localhost:9999"
auth: { type: bearer, token: "sk-..." }
timeout: 120
capabilities: [web_search, research]
Outbound — call other agents
The agent gets five tools:
a2a_discover(url)— what can this agent do?a2a_call(agent, message, context_id?)— send it a task, get the reply.a2a_list()— configured peers, saved conversations, metrics.a2a_history(context_id)— recall a saved A2A conversation.a2a_orchestrate(capability, message, mode?)— fan-out a task to every peer advertising a capability (all/first/best).
Inbound — be callable
When the a2a platform is enabled, Hermes serves a v1.0 Agent Card at
http://<host>:<port>/.well-known/agent-card.json (the legacy
/.well-known/agent.json path is also answered for pre-1.0 clients) and
accepts JSON-RPC
message/send, message/stream (SSE), tasks/get|list|cancel|subscribe,
and push notification configs (inline or via
tasks/pushNotificationConfig/create). Incoming tasks are injected into your
live agent session — the same agent that's talking to you, with full
memory — and the reply is returned over A2A. Completed tasks stay queryable
via tasks/get.
Security
- No token ⇒ localhost only. The server binds
127.0.0.1and refuses to widen unless you configure a token and setA2A_HOST. - Per-peer tokens:
A2A_PEER_TOKENS="alice:tok1,bob:tok2"gives each remote agent its own credential; that authenticated name (never anything in the request body) drives rate limiting, trust, and audit. - Inbound text — including
/-prefixed text — is run through prompt-injection filters and framed as untrusted peer input; remote peers cannot invoke operator slash commands. - Outbound text is scrubbed of credential-shaped strings.
- Push callbacks are SSRF-guarded and HMAC-SHA256 signed (
X-A2A-Signature). - Every exchange is logged to
~/.hermes/a2a_audit.jsonl. - Conversations persist to
~/.hermes/a2a_conversations/— they survive context compaction and restarts (a2a_historyrecalls them).
Env vars
| Var | Default | Meaning |
|---|---|---|
A2A_PEER_TOKENS |
(unset) | Per-peer credentials name:token,… (preferred). |
A2A_BEARER_TOKEN |
(unset) | Shared token; identity falls back to caller IP. |
A2A_HOST |
127.0.0.1 |
Bind host. Only widens with a token set. |
A2A_PORT |
9900 |
Inbound port. |
A2A_AGENT_NAME |
hostname-derived | Name on the Agent Card. |
A2A_PUBLIC_URL |
(unset) | Routable URL advertised on the card (reverse proxies). |
A2A_TRUSTED_PEERS |
(unset) | Allow-list of authenticated identities. |
A2A_ALLOW_ALL_USERS |
false |
Allow any authed peer (dev only). |
A2A_RATE_LIMIT |
60 |
Requests/minute per identity. |
A2A_MAX_PINGPONG_TURNS |
5 |
Anti-loop turn cap per context (max 20). |
A2A_REPLY_TIMEOUT |
300 |
Seconds to wait for the agent's reply; the orphan sweep never fails a task before this window (floor 300s) or while a request still waits on it. |
A2A_PUSH_SECRET |
bearer token | HMAC secret for push signing. |
A2A_ADVERTISED_TOOLSETS |
all registered | Restrict skills on the Agent Card. |
See DESIGN.md for architecture and the requirement-tracing table.