claude.md was eating 400 lines of subsystem detail that's useful
when you're working on that subsystem and noise the rest of the
time. split into:
- docs/conventions.md naming, identity, async forms, commit style
- docs/gotchas.md nspawn / nixos-container quirks
- docs/web-ui.md dashboard + per-agent layouts and endpoints
- docs/turn-loop.md claude invocation, wake prompt, mcp surface
- docs/approvals.md approval flow, manager policy, helper events
- docs/persistence.md sqlite dbs, retention, state dir layout
claude.md is now the entry point — file map, reading paths
("pick the doc that matches your task"), quick reminders that
fit on one screen, and a small scratchpad section for in-flight
context. references the docs; the docs don't reference claude.md.
no content was lost — the docs/ files cover everything the old
claude.md did, plus things i wrote up better while extracting.
118 lines
4.7 KiB
Markdown
118 lines
4.7 KiB
Markdown
# Turn loop + MCP
|
|
|
|
How the harness wakes up, what it asks claude to do, and what tools
|
|
claude has access to in return.
|
|
|
|
## The loop
|
|
|
|
Each agent harness (`hive-ag3nt serve` or `hive-m1nd serve`) runs:
|
|
|
|
1. Long-poll `Recv` on its socket. The host-side broker
|
|
(`broker.rs::recv_blocking`) returns immediately if there's a
|
|
pending message, otherwise waits up to 30 s for a broker `Sent`
|
|
event for this recipient.
|
|
2. Pop one message. Peek the remaining inbox depth with `Status`.
|
|
3. Emit `LiveEvent::TurnStart { from, body, unread }` onto the SSE
|
|
bus.
|
|
4. Spawn claude (one process per turn) and pipe the wake prompt
|
|
over stdin.
|
|
5. Stream stdout (JSON lines) into the bus as
|
|
`LiveEvent::Stream(value)`. Pump stderr as `Note`.
|
|
6. Wait for claude to exit. On `Prompt is too long`, run `/compact`
|
|
on the session once and retry the turn.
|
|
7. Emit `LiveEvent::TurnEnd { ok, note }`. Sleep `poll_ms` to avoid
|
|
tight loops on transient failures.
|
|
|
|
## The claude invocation
|
|
|
|
```
|
|
claude --print --verbose --output-format stream-json --model haiku \
|
|
--continue --settings /run/hive/claude-settings.json \
|
|
--system-prompt-file /run/hive/claude-system-prompt.md \
|
|
--mcp-config /run/hive/claude-mcp-config.json --strict-mcp-config \
|
|
--tools <builtins> --allowedTools <builtins+mcp>
|
|
# wake prompt piped over stdin
|
|
```
|
|
|
|
`--continue` keeps a persistent session per agent (claude stores
|
|
sessions in `~/.claude/projects/`, which is bind-mounted
|
|
persistently). Auto-compact and auto-memory are disabled via
|
|
`--settings` because hyperhive owns compaction (`/compact` on
|
|
overflow, retry once; operator can also force one via `/api/compact`).
|
|
|
|
The wake prompt is intentionally minimal: just the popped message's
|
|
`from`/`body`, plus an inline `({unread} more pending — drain via
|
|
…)` hint when `unread > 0`. Claude drives any further `recv`/`send`
|
|
itself via the embedded MCP server.
|
|
|
|
### On-boot files
|
|
|
|
`hive_ag3nt::turn::write_*` writes three files next to the per-agent
|
|
socket at `/run/hive/` once at startup:
|
|
|
|
- `claude-mcp-config.json` — re-invokes the running binary as `mcp`
|
|
child (so the same binary serves as harness + as claude's MCP
|
|
child process).
|
|
- `claude-settings.json` — the `--settings` blob (auto-compact and
|
|
auto-memory off, effortLevel medium).
|
|
- `claude-system-prompt.md` — rendered from
|
|
`hive-ag3nt/prompts/{agent,manager}.md` with `{label}`
|
|
substituted. Passed via `--system-prompt-file`.
|
|
|
|
The shared per-turn plumbing lives in `hive_ag3nt::turn::{write_mcp_config,
|
|
write_settings, write_system_prompt, run_turn, drive_turn,
|
|
emit_turn_end, wait_for_login, compact_session}` so the two binaries
|
|
can't drift.
|
|
|
|
## MCP surface
|
|
|
|
The harness ships an embedded MCP server (rmcp 1.7). Claude launches
|
|
it as a stdio child via `--mcp-config`. The hyperhive socket name is
|
|
`hyperhive`, so the tools land in claude as `mcp__hyperhive__<tool>`.
|
|
|
|
### Sub-agent tools
|
|
|
|
- `send(to, body)` — message a peer (logical agent name), another
|
|
agent, or the operator (recipient `operator`, surfaces in the
|
|
dashboard inbox).
|
|
- `recv()` — drain one inbox message.
|
|
|
|
### Manager tools (in addition to send/recv)
|
|
|
|
- `request_spawn(name)` — queue a Spawn approval for a brand-new
|
|
sub-agent (≤9 char name). Operator approves on the dashboard.
|
|
- `kill(name)` — graceful stop. No approval required.
|
|
- `start(name)` — start a stopped sub-agent. No approval.
|
|
- `restart(name)` — stop + start. No approval.
|
|
- `request_apply_commit(agent, commit_ref)` — submit a config
|
|
change for any agent (`hm1nd` for the manager's own config) for
|
|
operator approval.
|
|
- `ask_operator(question, options?, multi?)` — surface a question
|
|
on the dashboard. Non-blocking — returns the queued question id;
|
|
the operator's answer arrives later as
|
|
`HelperEvent::OperatorAnswered` in the manager inbox. Options
|
|
always render alongside a free-text fallback; `multi=true`
|
|
renders options as checkboxes.
|
|
|
|
The boundary: lifecycle ops on *existing* sub-agents
|
|
(`kill`/`start`/`restart`) are at the manager's discretion — no
|
|
operator approval. Creating a new agent (`request_spawn`) and
|
|
changing any agent's config (`request_apply_commit`) still go
|
|
through the approval queue.
|
|
|
|
### Tool envelope
|
|
|
|
`mcp::run_tool_envelope`: every MCP tool handler logs the request,
|
|
runs the body, logs the result. Pre-/post-log only — the inbox
|
|
status hint moved to the wake prompt + UI header.
|
|
|
|
### Tool whitelist (`mcp::ALLOWED_BUILTIN_TOOLS`)
|
|
|
|
- Allowed built-ins: `Bash`, `Edit`, `Glob`, `Grep`, `Read`,
|
|
`TodoWrite`, `Write`.
|
|
- Denied by omission: `WebFetch`, `WebSearch`, `Task`,
|
|
`NotebookEdit`.
|
|
- Allowed MCP tools: as listed above per flavor.
|
|
|
|
`Bash` is on the allow-list pending a finer-grained pattern allow-list
|
|
(`Bash(git *)`-style) — see [TODO](../TODO.md).
|