feat(hermes): Phase 2c — multi-turn history passed natively to all dispatch paths#267
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HongmingWang-Rabbit merged 1 commit intomainfrom Apr 15, 2026
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Completes the Phase 2 scope by keeping conversation turns as turns across
all three dispatch paths. Pre-2c, history was flattened into a single user
message via shared_runtime.build_task_text, which worked as a fallback but
lost the model's native multi-turn awareness (role attribution,
instruction-following on mid-conversation corrections, system-prompt
grounding against prior turns).
Phase 2a + 2b shipped the dispatch infrastructure + per-provider native
paths. This PR uses them properly.
## What's new
- **`_history_to_openai_messages(user_message, history)`** (static) — maps
A2A `(role, text)` tuples to OpenAI Chat Completions
`[{"role":"user"|"assistant","content":str}]`. Roles: `human`→`user`,
`ai`→`assistant`. Current turn appended as the final user message.
- **`_history_to_anthropic_messages`** (static) — identical wire shape to
OpenAI for text-only turns, so it delegates. Phase 2d tool_use/vision
blocks will diverge here.
- **`_history_to_gemini_contents`** (static) — Gemini uses a different
shape: `role="user"|"model"` (NOT "assistant") and text wrapped in
`parts=[{"text":...}]`. Delegates to none of the others.
- **`_do_openai_compat(user_message, history=None)`** — accepts history,
builds messages via `_history_to_openai_messages`. Back-compat: pass
`history=None` to get the old single-turn behavior.
- **`_do_anthropic_native(user_message, history=None)`** — same signature
change, calls `_history_to_anthropic_messages`. Still uses
`anthropic.AsyncAnthropic().messages.create()`, just with proper
multi-turn.
- **`_do_gemini_native(user_message, history=None)`** — same pattern,
calls `_history_to_gemini_contents`, passes to Gemini's
`generate_content(contents=...)`.
- **`_do_inference(user_message, history=None)`** — new signature,
dispatches by auth_scheme as before, passes both args through.
- **`execute()`** — no longer calls `build_task_text`. Calls
`extract_history(context)` directly and forwards to `_do_inference`.
Removes the `build_task_text` import (not needed in this file anymore).
## Tests
Existing 7 dispatch tests updated for the new `(user_message, history)`
signature — they assert the path is called with `("hello", None)` since
they pass no history.
5 NEW tests:
- `test_history_to_openai_messages_empty_history` — empty history degrades
to single user message (back-compat)
- `test_history_to_openai_messages_multi_turn` — round-trip of a 3-turn
history + current turn
- `test_history_to_anthropic_messages_same_as_openai` — cross-check that
anthropic path produces identical wire shape for text-only
- `test_history_to_gemini_contents_uses_model_role_and_parts_wrapper` —
verifies the Gemini-specific role mapping (`ai`→`model`) + parts wrapper
- `test_dispatch_passes_history_through` — end-to-end: _do_inference
forwards history to the chosen provider path
All 41 tests pass (15 Phase 2 dispatch + 26 Phase 1 registry):
pytest tests/test_hermes_phase2_dispatch.py tests/test_hermes_providers.py
41 passed in 0.07s
## Back-compat
- No public API changes to `create_executor()`. Callers that hit
`execute()` via A2A get the new multi-turn behavior automatically via
`extract_history(context)`.
- Callers that passed an empty history list (or None) get the same
single-turn behavior as pre-2c.
- The `build_task_text` helper in shared_runtime is unchanged — other
adapters (AutoGen, LangGraph) that use it keep working. Only Hermes
bypasses it now.
## What's NOT in this PR (Phase 2d)
- Tool calling / function calling on native paths (anthropic `tools=`,
gemini `tools=Tool(function_declarations=[...])`)
- Vision content blocks (image_url → anthropic `{type:"image", source:
{type:"base64",...}}` / gemini `{inline_data:{mime_type,data}}`)
- System instructions pass-through (anthropic `system=`, gemini
`system_instruction=`)
- Streaming (`astream_messages` / `streamGenerateContent` stream variants)
- Extended thinking (anthropic `thinking={"type":"enabled"}`) / Gemini
thinking config
Phase 2c is the **multi-turn upgrade**. Tool + vision + streaming are
Phase 2d, scoped in project_hermes_multi_provider.md.
## Related
- #240 Phase 2a (native Anthropic dispatch — in main)
- #255 Phase 2b (native Gemini dispatch — in main)
- Phase 1 (#208 — provider registry baseline, in main)
- `project_hermes_multi_provider.md` queued memory
- CEO 2026-04-15: "focus on supporting hermes agent"
HongmingWang-Rabbit
added a commit
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Apr 15, 2026
…ch paths
The Hermes adapter never read /configs/system-prompt.md. Any role that
switched to runtime: hermes was silently losing its role identity because
the system prompt wasn't passed to the model. This PR fixes that by:
1. HermesA2AExecutor.__init__ takes new optional `config_path` kwarg
2. `create_executor(config_path=...)` forwards to the constructor
3. `adapter.py` passes `config.config_path` through from AdapterConfig
4. `execute()` reads system-prompt.md via executor_helpers.get_system_prompt
(hot-reload-capable — reads on every turn, not just at startup)
5. `_do_inference(user_message, history, system_prompt)` — new arg threads
through the dispatch to each native path
6. Each path uses the provider's NATIVE system field:
- OpenAI-compat: prepends `{"role":"system", "content":...}` to messages
- Anthropic: top-level `system=` kwarg (NOT in messages — Anthropic
requires system at the top level)
- Gemini: `config=GenerateContentConfig(system_instruction=...)`
## Phase scoreboard
- 2a (in main) — native Anthropic dispatch infra
- 2b (in main) — native Gemini dispatch
- 2c (in main) — multi-turn history on all paths
- **2d-i (this PR)** — system prompts on all paths
- 2d-ii (future) — tool calling on native paths
- 2d-iii (future) — vision content blocks on native paths
- 2d-iv (future) — streaming
## Test coverage
46/46 tests pass (20 Phase 2 dispatch + 26 Phase 1 registry):
- Existing dispatch tests updated to assert the 3-arg call shape
`("hello", None, None)` — history + system_prompt both None
- 4 new tests:
- `dispatch_passes_system_prompt_to_anthropic` — happy path, third arg flows
- `dispatch_passes_system_prompt_to_gemini` — happy path
- `dispatch_passes_system_prompt_to_openai` — happy path
- `executor_accepts_config_path_kwarg` — constructor stores config_path
- `create_executor_forwards_config_path` — both back-compat and registry
resolution paths forward config_path through to the executor
## Back-compat
- `config_path=None` (default) → execute() skips system-prompt injection,
same behavior as pre-2d-i
- Workspaces with `runtime: hermes` but no `/configs/system-prompt.md`
file get `system_prompt=None` (get_system_prompt returns fallback),
same as before
- The 13 OpenAI-compat providers work identically — system_prompt just
adds a leading message, which every OpenAI-compat endpoint already
supports
- Anthropic + Gemini previously got zero system context; now they get
the same system prompt the workspace's system-prompt.md carries
## Why this matters
Before this PR: if someone flipped a workspace from `runtime: claude-code`
to `runtime: hermes`, the agent would act generically (no role identity,
no project conventions, no CLAUDE.md context) because the Hermes executor
never looked at system-prompt.md. That's a silent correctness regression
the test suite wouldn't catch because none of our live workspaces use
the hermes runtime today.
With this PR: Hermes workspaces get the same system prompt injection as
Claude-code workspaces, making the `runtime: hermes` switch a true drop-in
alternative.
## Related
- #267 Phase 2c (multi-turn history — in main)
- #255 Phase 2b (gemini native — in main)
- #240 Phase 2a (anthropic native — in main)
- #208 Phase 1 (provider registry — in main)
- project_hermes_multi_provider.md — Phase 2d-i was the next queued item
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Why
Phase 2a + 2b landed the native Anthropic + Gemini dispatch infrastructure. But both native paths were still receiving a flattened single-turn `task_text` built via `shared_runtime.build_task_text`, which concatenates prior conversation into one user blob. The model's native multi-turn awareness (role attribution, instruction-following across turns, system-prompt grounding) is lost.
This PR keeps turns as turns on all 3 paths.
Change shape
Back-compat
Test coverage
41/41 tests pass (15 Phase 2 dispatch + 26 Phase 1 registry). 5 new history tests:
Existing 7 dispatch tests updated for the new `(user_message, history)` signature (now assert called with `("hello", None)`).
What's NOT in this PR (Phase 2d)
Phase 2c is multi-turn only. Tool + vision + streaming = Phase 2d, scoped in `project_hermes_multi_provider.md`.
Related