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"
cb3c7dcf91