Files
hermes-agent/agent/system_prompt.py
kshitijk4poor defdf64790 simplify(agent): surface switch — reuse flatten_message_text / agent_tool_names / one runtime-boundary split
- _transcript_row_texts re-implemented agent.message_content.flatten_message_text
  and the api_content sidecar rule; the note can only land on a user row,
  so the transcript scan now skips assistant/tool rows (the bulk of the bytes).
- Three sites computed "names of agent.tools"; tools.mcp_tool_agent gains
  agent_tool_names() used by the switch note and conversation_loop, which
  also stops importing the private _def_name across modules. The name list
  is only captured when a switch was announced.
- split_runtime_boundary() is the single owner of the runtime-block
  rpartition/END check for both identity_line_value and
  _stored_prompt_matches_runtime.
- platform_surface_hint was a public alias of _platform_hint; the function is
  now platform_hint (its docstring pointed at the pre-move module).
- consume_gateway_turn_context_notes and consume_surface_switch_note share
  _pop_turn_note so the two one-shot channels have identical semantics.
- platform check hoisted above the transcript scan.
2026-09-09 10:31:26 +05:30

762 lines
40 KiB
Python

"""System-prompt assembly for :class:`AIAgent`.
Built once per session and reused across turns (only context compression
triggers a rebuild) so the upstream prefix cache stays warm. Three tiers are
joined with ``\\n\\n``: ``stable`` (identity, guidance, env hints, coding brief,
platform hints), ``context`` (workspace snapshot, caller ``system_message``,
context files) and ``volatile`` (skills index, memory, USER.md, external memory
provider, timestamp line). See ``references/system-prompt-invariant.md``.
"""
from __future__ import annotations
import json
import logging
import os
import re
from pathlib import Path
from typing import Any, Dict, List, Optional, Tuple
from agent.prompt_builder import (
DEFAULT_AGENT_IDENTITY, EXECUTION_GUIDANCE_MODELS, GOOGLE_MODEL_OPERATIONAL_GUIDANCE,
HERMES_AGENT_HELP_GUIDANCE, HERMES_AGENT_HELP_GUIDANCE_NO_SKILLS, KANBAN_GUIDANCE,
PARALLEL_TOOL_CALL_GUIDANCE, PLATFORM_HINTS, SESSION_SEARCH_GUIDANCE,
SKILLS_GUIDANCE, STEER_CHANNEL_NOTE, TASK_COMPLETION_GUIDANCE, TELEGRAM_RICH_MESSAGES_HINT,
TOOL_USE_ENFORCEMENT_GUIDANCE, TOOL_USE_ENFORCEMENT_MODELS, drain_truncation_warnings,
)
from agent import prompt_builder as _pb
from agent.runtime_cwd import resolve_context_cwd
from hermes_constants import get_default_hermes_root, get_hermes_home
from utils import is_truthy_value
logger = logging.getLogger(__name__)
_PLUGIN_SECTION_FRAME_RE = re.compile(
r"^## Plugin Context: (?P<id>[a-z0-9][a-z0-9._-]{0,127})\n<!-- hermes-plugin-section-chars:(?P<chars>[0-9]{1,4}) -->\n\n",
re.MULTILINE,
)
_GATE_WORDS = {**dict.fromkeys(("true", "always", "yes", "on"), True), **dict.fromkeys(("false", "never", "no", "off"), False)}
def _model_gate(setting: Any, model: Optional[str], default_models) -> bool:
"""Resolve a config gate: True/"true"-ish -> on, False/"false"-ish -> off,
list -> case-insensitive model-substring match, anything else ("auto") ->
match against *default_models*."""
if setting is True or setting is False:
return setting
if isinstance(setting, str) and setting.lower() in _GATE_WORDS:
return _GATE_WORDS[setting.lower()]
model_lower = (model or "").lower()
if isinstance(setting, list):
return any(p.lower() in model_lower for p in setting if isinstance(p, str))
return any(p in model_lower for p in default_models)
def _resolve_platform_hint(agent: Any, platform_key: str, default_hint: str) -> str:
"""Apply the ``platform_hints.<platform>`` config override: ``replace``
substitutes the default, ``append`` adds text (a bare string is shorthand
for append). Malformed entries fall back to the unmodified default so bad
config can never break prompt assembly or leak across platforms."""
overrides = getattr(agent, "_platform_hint_overrides", None)
spec = overrides.get(platform_key) if platform_key and isinstance(overrides, dict) else None
if isinstance(spec, str):
spec = {"append": spec}
if not isinstance(spec, dict):
return default_hint
replace_text, append_text = (v.strip() if isinstance(v, str) else "" for v in (spec.get("replace"), spec.get("append")))
base = replace_text or default_hint
return f"{base}\n\n{append_text}".strip() if append_text else base
_TUI_EMBEDDED_PANE_CLARIFIER = (
" You're in its embedded terminal pane, beside the GUI chat — the user can "
"select your output (Option-drag on macOS, Shift-drag elsewhere) and press "
"Cmd/Ctrl+L to send it to the chat composer."
)
def _tui_embedded_pane_clarifier(hint: str) -> str:
"""Append the desktop embedded-terminal clarifier when ``HERMES_DESKTOP_TERMINAL``
is set (only the desktop's TUI PTY, never the chat backend). Idempotent."""
if not hint or _TUI_EMBEDDED_PANE_CLARIFIER in hint or not is_truthy_value(os.getenv("HERMES_DESKTOP_TERMINAL")):
return hint
return hint + _TUI_EMBEDDED_PANE_CLARIFIER
def _plugin_session_info(agent: Any) -> Dict[str, str]:
"""Return immutable-at-render-time metadata exposed to prompt sections."""
try:
cwd = str(resolve_context_cwd() or "")
except Exception:
cwd = ""
info = {k: str(getattr(agent, k, None) or "") for k in ("session_id", "model", "provider", "platform")}
info.update(profile_name=_active_profile_name(agent, _ambient_plugin_profile_name), cwd=cwd)
return info
def _ambient_plugin_profile_name() -> str:
from hermes_cli.profiles import get_active_profile_name
return str(get_active_profile_name() or "default")
def _active_profile_name(agent: Any, ambient) -> str:
"""Profile name from the agent's OWN home, else *ambient()*; "default" on any
failure. Ambient resolution misreports on threads that lost the HERMES_HOME
ContextVar, which is why the agent's home is preferred."""
try:
home = _agent_home(agent)
return _profile_name_for_home(home) if home is not None else ambient()
except Exception:
return "default"
def _frozen_plugin_prompt_sections(agent: Any) -> tuple:
"""Render plugin sections once per session and freeze them on the agent.
A restored ``_cached_system_prompt`` is parsed instead of re-running plugin
code; a render that raises at a rebuild boundary keeps the previous bytes
(stashed by ``invalidate_system_prompt``) instead of silently vanishing."""
if hasattr(agent, "_plugin_system_prompt_sections_snapshot"):
return agent._plugin_system_prompt_sections_snapshot
stored_prompt = getattr(agent, "_cached_system_prompt", None)
if isinstance(stored_prompt, str) and stored_prompt:
rendered = _restore_plugin_prompt_sections(stored_prompt)
else:
try:
from hermes_cli.plugins import render_system_prompt_sections
rendered = tuple(render_system_prompt_sections(_plugin_session_info(agent)))
except Exception as exc:
rendered = getattr(agent, "_plugin_system_prompt_sections_previous", None)
if rendered:
logger.warning("Plugin system prompt sections failed to re-render (%s); keeping the previous frozen sections", exc)
else:
logger.warning("Plugin system prompt sections could not be rendered: %s", exc)
rendered = ()
agent._plugin_system_prompt_sections_snapshot = rendered
return rendered
def _restore_plugin_prompt_sections(prompt: str) -> tuple:
"""Recover frozen section bytes from the persisted full prompt. Only the
exact canonical container emitted by core is accepted — user/project text
may resemble a frame."""
from hermes_cli.plugins import (
MAX_SYSTEM_PROMPT_SECTION_CHARS, PLUGIN_SECTIONS_END, PLUGIN_SECTIONS_START,
RenderedPluginSystemPromptSection, format_system_prompt_sections,
)
start = prompt.rfind(PLUGIN_SECTIONS_START)
end = prompt.find(PLUGIN_SECTIONS_END, start + len(PLUGIN_SECTIONS_START)) if start >= 0 else -1
if end < 0:
return ()
after_end = end + len(PLUGIN_SECTIONS_END)
if not prompt[after_end:].startswith("\n\nConversation started:"):
return ()
framed = prompt[start:after_end]
restored = []
for match in _PLUGIN_SECTION_FRAME_RE.finditer(framed):
content_len = int(match.group("chars"))
content = framed[match.end() : match.end() + content_len]
if content_len > MAX_SYSTEM_PROMPT_SECTION_CHARS or len(content) != content_len:
continue
restored.append(RenderedPluginSystemPromptSection(id=match.group("id"), content=content,
position="after_memory", plugin="persisted-prompt"))
return tuple(restored) if format_system_prompt_sections(restored) == framed else ()
def restore_plugin_prompt_sections(agent: Any, prompt: str) -> None:
"""Seed a resumed agent's frozen snapshot from persisted prompt bytes."""
agent._plugin_system_prompt_sections_snapshot = _restore_plugin_prompt_sections(prompt)
def _plugin_section_blocks(sections: tuple, position: str) -> List[str]:
from hermes_cli.plugins import format_system_prompt_sections
block = format_system_prompt_sections([s for s in sections if s.position == position])
return [block] if block else []
def _session_start_like(agent: Any, now: Any) -> Any:
"""Best-known conversation start time, or ``now`` as a fallback.
``Conversation started:`` must be byte-stable across rebuilds (compression,
resume, fresh gateway turns), so prefer immutable sources in order: the
lineage-root session id's embedded stamp (compaction rotates ids, each with
its own mint time), the current session id's stamp, ``agent.session_start``,
then ``now``. Stamps are box-local wall-clock: attach that zone first, then
convert to ``now``'s zone so the date matches the per-turn clock.
0. the LINEAGE-ROOT session id's embedded timestamp — compaction can rotate the session id, and each
rotated id embeds its OWN mint time, so after months of compactions rung 1 alone would quietly re-birth
the conversation at its latest rotation. Walking to the lineage root (same walk as
``_conversation_root_id``) recovers the ORIGINAL birth stamp — a Bot Mode forever-chat keeps knowing
when it was first born, across every compaction (maintainer-directed, #98426); 1. the timestamp embedded
in ``session_id`` (``YYYYMMDD_HHMMSS_...``) — immutable for the life of the session, so the line is
byte-stable across every rebuild boundary (preserving prefix-cache KV); 2. 3. ``now`` (initial/legacy
build without either).
"""
from datetime import datetime
def _to_display_tz(dt: Any) -> Any:
if dt.tzinfo is None:
try:
dt = dt.replace(tzinfo=datetime.now().astimezone().tzinfo)
except (ValueError, OSError):
pass
if getattr(now, "tzinfo", None) is not None and dt.tzinfo is not None:
try:
dt = dt.astimezone(now.tzinfo)
except (ValueError, OSError):
pass
return dt
session_id = getattr(agent, "session_id", None)
db = getattr(agent, "_session_db", None)
try:
root_id = db.get_conversation_root(session_id) if db is not None and isinstance(session_id, str) and session_id else None
except Exception:
root_id = None
for candidate in (root_id, session_id):
m = re.match(r"^(\d{8})_(\d{6})", candidate) if isinstance(candidate, str) else None
if m:
try:
return _to_display_tz(datetime.strptime(f"{m.group(1)}_{m.group(2)}", "%Y%m%d_%H%M%S"))
except ValueError:
pass
session_start = getattr(agent, "session_start", None)
return _to_display_tz(session_start) if hasattr(session_start, "astimezone") else now
def _agent_home(agent: Any) -> Optional[Path]:
"""The agent's OWN profile home, or None to use ambient resolution.
A bound HERMES_HOME ContextVar override wins (the gateway multiplexes
profiles over one shared session DB and binds the home per turn); else the
parent of ``_session_db.db_path`` — ground truth on threads that lost the
ContextVar, where ambient resolution would leak the launch profile.
1. Surfaces that multiplex several profiles over ONE shared session DB (the messaging gateway:
``gateway/run.py`` hands every agent the launch-home ``state.db`` and binds the profile home per turn
via ``_profile_runtime_scope`` + ``copy_context``) would otherwise have the db-derived launch home STOMP
the correctly-bound profile — inverting the leak this helper exists to fix (found by @kshitijk4poor's
post-merge probe on #86313). 2. Fallback: the home containing the agent's ``_session_db.db_path``
(``<home>/state.db``) — ground truth on threads that lost the ContextVar (ContextVars don't propagate
into ``threading.Thread``), where the unbound build previously fell back to the launch home and leaked
the default profile's skills/identity into a bot prompt.
"""
try:
from hermes_constants import get_hermes_home_override
override = get_hermes_home_override()
if override:
return Path(override)
except Exception:
pass
try:
db_path = getattr(getattr(agent, "_session_db", None), "db_path", None)
return Path(db_path).parent if db_path else None
except Exception:
return None
def _agent_skills_dir(agent: Any) -> Optional[Path]:
"""The agent's own ``<home>/skills`` dir, or None to use ambient home."""
home = _agent_home(agent)
return home / "skills" if home is not None else None
def _profile_name_for_home(home: Path) -> str:
"""``<root>/profiles/X`` -> ``"X"``; anything else -> ``"default"``.
Uses ``get_default_hermes_root()`` (NOT ``get_hermes_home()``): on a bound
profile session the ambient home IS the profile dir, so every profile
would misreport as "default"."""
try:
from hermes_constants import get_default_hermes_root
rel = home.resolve().relative_to((get_default_hermes_root() / "profiles").resolve())
return rel.parts[0] if rel.parts else "default"
except (ValueError, OSError):
return "default"
def _tool_guidance_block(agent: Any) -> Optional[str]:
"""Tool-aware behavioral guidance, injected only when the tools are loaded."""
names = agent.valid_tool_names
# With both memory stores disabled no store is built, so the full guidance
# would steer the model at a tool that always answers "Memory is not
# available"; with only USER.md enabled the narrower block is used.
memory_guidance = None
if "memory" in names:
memory_guidance = _pb.build_memory_guidance(
getattr(agent, "_memory_enabled", True),
getattr(agent, "_user_profile_enabled", True),
skill_manage_available="skill_manage" in names,
)
# Kanban lifecycle: resolved once at __init__ (_kanban_worker_guidance);
# the kanban_show fallback covers code paths that bypass agent_init.
_kanban_guidance = getattr(agent, "_kanban_worker_guidance", None)
if _kanban_guidance is None and "kanban_show" in names:
_kanban_guidance = KANBAN_GUIDANCE
tool_guidance = [
memory_guidance,
SESSION_SEARCH_GUIDANCE if "session_search" in names else None,
SKILLS_GUIDANCE if "skill_manage" in names else None,
_kanban_guidance,
]
return " ".join(g for g in tool_guidance if g) or None
def _skills_prompt(agent: Any) -> str:
"""Skills index (empty without skills tools). Focus mode demotes non-coding
categories to names-only — never hidden, every name stays visible."""
if not any(name in agent.valid_tool_names for name in ['skills_list', 'skill_view', 'skill_manage']):
return ""
import model_tools
avail_toolsets = {model_tools.get_toolset_for_tool(tool_name) for tool_name in agent.valid_tool_names} - {None, ""}
try:
from agent.coding_context import coding_compact_skill_categories
_compact_cats = coding_compact_skill_categories(platform=agent.platform, cwd=resolve_context_cwd())
except Exception:
_compact_cats = frozenset()
return _pb.build_skills_system_prompt(available_tools=agent.valid_tool_names, available_toolsets=avail_toolsets,
compact_categories=_compact_cats or None, skills_dir_override=_agent_skills_dir(agent))
def _bot_mode_parts(agent: Any) -> List[str]:
"""Bot Mode teammate protocol — only in a bot's canonical "Bot Chat" session.
Marks the prompt timeless (the volatile date line is dropped) since a birth
date pinned in a months-long session is misinformation."""
parts: List[str] = []
try:
from tools.bot_mode_probe import BOT_CHAT_TITLE, epoch_line, get_bot_mode_protocol_section
_title = str(getattr(agent, "_session_title_hint", "") or "").strip()
if not _title:
_sdb = getattr(agent, "_session_db", None)
_sid = getattr(agent, "session_id", None)
_title = str((_sdb.get_session_title(_sid) if (_sdb and _sid) else None) or "").strip()
_bot_section = get_bot_mode_protocol_section(_agent_home(agent)) if _title == BOT_CHAT_TITLE else None
if _bot_section:
parts.append(_bot_section)
# Capability epoch lets the restore path rebuild ONCE per
# user-initiated capability change in an eternal session.
parts.append(epoch_line(_agent_home(agent)))
agent._bot_chat_timeless_prompt = True
except Exception:
pass
return parts
def _ambient_file_safety_profile_name() -> str:
from agent.file_safety import _resolve_active_profile_name
return _resolve_active_profile_name()
def _active_profile_line(agent: Any) -> str:
"""Name the running profile so the agent doesn't conflate ``~/.hermes/skills``
(default) with ``~/.hermes/profiles/<active>/skills``. Resolved from the
agent's OWN home first (a build thread that lost the ContextVar would
otherwise print "default" for a bot profile)."""
_agent_home_path = _agent_home(agent)
active_profile = _active_profile_name(agent, _ambient_file_safety_profile_name)
if active_profile == "default":
# With an explicit agent home, the default profile's data lives at the
# ROOT (get_hermes_home() on a bound profile session is the PROFILE dir).
# Without one, keep the ambient (patchable) resolution byte-identical.
_root_str = str(get_default_hermes_root() if _agent_home_path is not None else get_hermes_home())
return (
"Active Hermes profile: default. Other profiles (if any) live "
"under " + _root_str + "/profiles/<name>/. Each profile has its own "
"skills/, plugins/, cron/, and memories/ that affect a different "
"session than this one. Do not modify another profile's "
"skills/plugins/cron/memories unless the user explicitly directs "
"you to."
)
# A non-default name is only returned when the resolved home is ALREADY
# <root>/profiles/<name>, so the profile home is the session home itself.
profile_home = str(_agent_home_path) if _agent_home_path is not None else str(get_hermes_home())
# A non-default name is only ever returned when the resolved home is ALREADY <root>/profiles/<name> —
# that is exactly how both _profile_name_for_home() and _resolve_active_profile_name() derive it. So the
# profile home is the session home itself; appending /profiles/<name> again doubled it (#72894). The
# default profile's data sits at the ROOT (get_default_hermes_root()), which in ambient profile mode is
# NOT get_hermes_home().
default_root = get_default_hermes_root()
return (
f"Active Hermes profile: {active_profile}. This session reads "
f"and writes {profile_home}/. The default "
f"profile's data lives at {default_root}/skills/, {default_root}/plugins/, "
f"{default_root}/cron/, {default_root}/memories/ — those belong to a "
f"different session run from a different shell. Do NOT modify "
f"another profile's skills/plugins/cron/memories unless the user "
f"explicitly directs you to."
)
def platform_hint(agent: Any) -> str:
"""Built-in/plugin platform hint + Telegram rich-messages opt-in + config
override + desktop TUI clarifier."""
platform_key = (agent.platform or "").lower().strip()
_default_hint = PLATFORM_HINTS.get(platform_key, "")
if not _default_hint and platform_key:
try:
from gateway.platform_registry import platform_registry
_entry = platform_registry.get(platform_key)
_default_hint = (_entry and _entry.platform_hint) or ""
except Exception:
pass
if platform_key == "telegram" and _default_hint and _telegram_rich_messages_enabled():
_default_hint = _default_hint.rstrip() + " " + TELEGRAM_RICH_MESSAGES_HINT
_effective_hint = _resolve_platform_hint(agent, platform_key, _default_hint)
if platform_key == "tui" and _effective_hint:
_effective_hint = _tui_embedded_pane_clarifier(_effective_hint)
return _effective_hint
def _telegram_rich_messages_enabled() -> bool:
"""``rich_messages`` from the Telegram ``extra`` config; same precedence the
adapter uses (top-level ``platforms.telegram.extra`` overrides
``gateway.platforms.telegram.extra`` at the leaf). False on any read failure."""
try:
from hermes_cli.config import load_config_readonly
_cfg = load_config_readonly()
_gw = (((_cfg.get("gateway") or {}).get("platforms") or {}).get("telegram") or {}).get("extra")
_top = ((_cfg.get("platforms") or {}).get("telegram") or {}).get("extra")
merged = {**(_gw if isinstance(_gw, dict) else {}), **(_top if isinstance(_top, dict) else {})}
return bool(merged.get("rich_messages"))
except Exception:
return False
def _zone_bits(now: Any, tz: Any) -> List[str]:
"""IANA key, abbreviation (if different) and UTC offset — all constant for
the day, so the byte-stable date line stays cacheable."""
_iana = getattr(tz, "key", None)
_abbrev = now.strftime("%Z")
_offset = now.strftime("%z") # '-0400' -> 'UTC-04:00'
bits = [_iana] if _iana else []
if _abbrev and _abbrev != _iana:
bits.append(_abbrev)
if _offset:
bits.append(f"UTC{_offset[:3]}:{_offset[3:]}")
return bits
def _timestamp_line(agent: Any) -> str:
"""Date-only so the prompt is byte-stable for the day; zone + offset so
tools needn't guess EST vs EDT. Long-lived sessions get an "as of" line on
rebuild days (the cache prefix is already invalidated at that boundary)."""
from hermes_time import get_timezone as _hermes_tz, now as _hermes_now
now = _hermes_now()
_bits = _zone_bits(now, _hermes_tz())
_zone_suffix = f" ({', '.join(_bits)})" if _bits else ""
_start = _session_start_like(agent, now)
timestamp_line = f"Conversation started: {_start.strftime('%A, %B %d, %Y')}{_zone_suffix}"
# Second line (maintainer design, salvaging #96224's anchor): long-lived sessions — Bot Mode
# forever-chats, messenger channels people never close — span many days and many compactions. A lone
# birth date leads the model to believe it is still living in that old day. The prompt is rebuilt at
# every compaction boundary, so stamp the rebuild day too: 'started' stays anchored and byte-stable, 'as
# of' refreshes exactly when the cache prefix is already being invalidated (compaction), so the added
# line costs no extra cache churn. Same-day sessions skip the second line entirely — nothing to correct,
# and the single-line shape stays byte-identical for the day (prefix-cache safe).
if now.strftime("%Y%m%d") != _start.strftime("%Y%m%d"):
timestamp_line += (f"\nToday's date (as of the last context rebuild): {now.strftime('%A, %B %d, %Y')} "
"— trust this over the start date for what day it is now; query tools for exact time.")
if getattr(agent, "_bot_chat_timeless_prompt", False):
timestamp_line = f"Timezone: {', '.join(_bits)}" if _bits else ""
trailer = (("Session ID", agent.session_id if agent.pass_session_id else None), ("Model", agent.model),
("Provider", agent.provider), ("Platform", agent.platform))
return timestamp_line + "".join(f"\n{label}: {value}" for label, value in trailer if value)
def _memory_parts(agent: Any) -> List[str]:
"""Built-in memory/USER.md blocks plus the external provider block (gated on
the same check ``inject_memory_provider_tools`` uses, so we never advertise
tools the toolset config gated off)."""
parts: List[str] = []
if agent._memory_store:
for enabled, kind in ((agent._memory_enabled, "memory"), (agent._user_profile_enabled, "user")):
block = agent._memory_store.format_for_system_prompt(kind) if enabled else None
if block:
parts.append(block)
# External memory provider system prompt block (additive to built-in). Gated on the same check
# ``inject_memory_provider_tools`` uses so we never advertise provider tools that the agent's toolset
# configuration has already gated off (#81014).
if agent._memory_manager:
try:
from agent.memory_manager import memory_provider_tools_exposed as _mem_exposed
except Exception:
_mem_exposed = None
if _mem_exposed is None or _mem_exposed(agent):
try:
_ext_mem_block = agent._memory_manager.build_system_prompt()
except Exception:
_ext_mem_block = None
if _ext_mem_block:
parts.append(_ext_mem_block)
return parts
def _identity_parts(agent: Any, ctx_len: Optional[int]) -> Tuple[List[str], bool]:
"""SOUL.md (primary identity; cron keeps the persona while skipping cwd
instructions, scoped to the agent's OWN home) or the default identity.
Returns ``(parts, soul_loaded)``."""
wants_soul = agent.load_soul_identity or not agent.skip_context_files
_soul_content = _pb.load_soul_md(ctx_len, home_override=_agent_home(agent)) if wants_soul else None
return ([_soul_content], True) if _soul_content else ([DEFAULT_AGENT_IDENTITY], False)
def _guidance_parts(agent: Any) -> List[str]:
"""Universal + tool-aware + model-gated guidance blocks, each gated by its config.yaml key."""
parts: List[str] = []
if agent.valid_tool_names:
parts += [
text for flag, text in (
("_task_completion_guidance", TASK_COMPLETION_GUIDANCE),
("_parallel_tool_call_guidance", PARALLEL_TOOL_CALL_GUIDANCE),
) if getattr(agent, flag, True)
]
parts.append(_tool_guidance_block(agent)) # None/empty entries are dropped by _join_tier
if not agent.valid_tool_names:
return parts
# Steering only lands inside tool results, so only reachable with tools.
parts.append(STEER_CHANNEL_NOTE)
# agent.tool_use_enforcement / agent.execution_guidance: "auto" (default)
# matches the hardcoded model lists; true/false force; a list gives custom
# model-name substrings. Execution guidance is an independent gate so
# DeepSeek/Kimi/Qwen-class models get it even with enforcement off.
if _model_gate(agent._tool_use_enforcement, agent.model, TOOL_USE_ENFORCEMENT_MODELS):
parts.append(TOOL_USE_ENFORCEMENT_GUIDANCE)
if any(g in (agent.model or "").lower() for g in ("gemini", "gemma")):
parts.append(GOOGLE_MODEL_OPERATIONAL_GUIDANCE)
if _model_gate(getattr(agent, "_execution_guidance", "auto"), agent.model, EXECUTION_GUIDANCE_MODELS):
from agent.prompt_builder import execution_guidance_text
parts.append(execution_guidance_text(agent.valid_tool_names))
return parts
def _alibaba_identity_part(agent: Any) -> List[str]:
"""Alibaba Coding Plan always reports "glm-4.7" as the model name; inject
the real identity so the agent can answer correctly."""
if agent.provider != "alibaba":
return []
_model_short = agent.model.rsplit("/", 1)[-1]
return [
f"You are powered by the model named {_model_short}. "
f"The exact model ID is {agent.model}. "
f"When asked what model you are, always answer based on this information, "
f"not on any model name returned by the API."
]
def _coding_parts(agent: Any) -> Tuple[List[str], List[str], List[str]]:
"""``(prefix, workspace, trailing)`` coding-posture blocks; all empty
without tools or when probing fails (it must never block prompt build).
The workspace block is a live git probe after project context, ahead of the whole
volatile band; re-probing at the compaction rebuild re-emits different bytes for any
repo that moved and defeats the keep-prompt fast path. So the bytes are pinned per
session on the agent, keyed by the resolved cwd (a gateway serves many cwds), and
replayed on rebuilds; ``reset_session_state`` drops the pin at a session boundary.
"""
try:
from agent.coding_context import coding_system_prompt_parts
if not agent.valid_tool_names:
return [], [], []
cwd = resolve_context_cwd()
cwd_key = str(cwd) if cwd is not None else ""
pinned = getattr(agent, "_frozen_workspace_snapshot", None)
# "" is a real pinned value (no workspace here) — only a cwd mismatch re-probes.
replay = pinned[1] if pinned is not None and pinned[0] == cwd_key else None
parts = coding_system_prompt_parts(platform=agent.platform, cwd=cwd, model=agent.model,
valid_tool_names=agent.valid_tool_names, workspace_block=replay)
if replay is None:
agent._frozen_workspace_snapshot = (cwd_key, parts[1][0] if parts[1] else "")
return parts
except Exception:
pass
return [], [], []
def _post_workspace_parts(agent: Any) -> List[str]:
"""Blocks that follow the worktree-specific context: environment probe
(config.yaml agent.environment_probe; one line, nothing when clean, skipped
for remote backends), bot-mode protocol, profile line, platform hint."""
parts: List[str] = []
if getattr(agent, "_environment_probe", True):
try:
from tools.env_probe import get_environment_probe_line
parts.append(get_environment_probe_line())
except Exception:
pass # Probe failure must never block prompt build.
if getattr(agent, "_bot_mode_protocol", True):
parts.extend(_bot_mode_parts(agent))
parts += [_active_profile_line(agent), platform_hint(agent)]
return parts
def _context_files_part(agent: Any, ctx_len: Optional[int], soul_loaded: bool) -> List[str]:
"""Project context files (AGENTS.md etc.) for the context tier. TERMINAL_CWD
when set (gateway); None lets discovery fall back to the launch dir. The
install-tree fallback is only legitimate for cli/tui where the launch dir
IS the user's shell cwd; desktop-pinned launch dirs are treated as the
fallback they really are so the guard can reject Hermes's bundled AGENTS.md."""
if agent.skip_context_files:
return []
launch_artifact = getattr(agent, "_context_cwd_is_launch_artifact", False)
return [_pb.build_context_files_prompt(
cwd=None if launch_artifact else resolve_context_cwd(), skip_soul=soul_loaded, context_length=ctx_len,
allow_install_tree_fallback=agent.platform in ("cli", "tui"), home_override=_agent_home(agent))]
def _join_tier(parts: List[Optional[str]]) -> str:
"""Join non-empty parts; None/blank entries are dropped."""
return "\n\n".join(p.strip() for p in parts if p and p.strip())
def build_system_prompt_parts(agent: Any, system_message: Optional[str] = None) -> Dict[str, str]:
"""Assemble the system prompt as three ordered cache tiers: ``stable`` (identity,
guidance and the coding brief), ``context`` (caller ``system_message``, project
context files, workspace snapshot and remaining workspace guidance) and
``volatile`` (skills index, memory, user profile, external memory block,
timestamp line, runtime environment hints). Worktree-dependent blocks follow project context so a
shared context file can remain in the longest common prefix across worktrees.
Never re-rendered mid-session."""
# Model context window scales the context-file caps; stable per conversation.
_cc_len = getattr(getattr(agent, "context_compressor", None), "context_length", None)
_ctx_len = _cc_len if isinstance(_cc_len, int) and _cc_len > 0 else None
# ── Stable tier ────────────────────────────────────────────────
stable_parts, _soul_loaded = _identity_parts(agent, _ctx_len)
# The skill_view() pointer dangles without skill tools OR without the
# hermes-agent skill installed, so the variant is chosen after the skills
# index is built; this slot holds its position.
_help_guidance_slot = len(stable_parts)
stable_parts.append(HERMES_AGENT_HELP_GUIDANCE_NO_SKILLS)
stable_parts.extend(_guidance_parts(agent))
skills_prompt = _skills_prompt(agent)
# Skill-pointer variant requires BOTH skill_view AND the hermes-agent skill
# in the rendered index (pure string check — inherits the index's stability).
if "skill_view" in (agent.valid_tool_names or set()) and "- hermes-agent:" in skills_prompt:
stable_parts[_help_guidance_slot] = HERMES_AGENT_HELP_GUIDANCE
stable_parts.extend(_alibaba_identity_part(agent))
# Coding posture: the operating brief stays in the stable prefix. The
# environment block contains the current cwd/backend and belongs after
# project context, not ahead of a large shared AGENTS.md block.
environment_hints = _pb.build_environment_hints()
coding_prefix_parts, coding_workspace_parts, coding_trailing_parts = _coding_parts(agent)
stable_parts.extend(coding_prefix_parts)
post_workspace_parts = _post_workspace_parts(agent)
# ── Context tier (project/worktree-dependent, may change between sessions) ──
context_parts: List[str] = []
# ephemeral_system_prompt is injected at API-call time only, never cached.
if system_message is not None:
context_parts.append(system_message)
context_parts.extend(_context_files_part(agent, _ctx_len, _soul_loaded))
if coding_workspace_parts:
context_parts.extend([*coding_workspace_parts, *coding_trailing_parts, *post_workspace_parts])
else:
# Preserve the stable placement for non-workspace sessions; there is no
# worktree snapshot whose later position would improve their prefix.
stable_parts.extend([*coding_trailing_parts, *post_workspace_parts])
# ── Volatile tier (most likely to differ on a rebuild; kept last so the stable prefix stays reusable) ──
# Skills are runtime-mutable, so the index leads the volatile band: on a longest-prefix
# backend an unchanged index stays inside the reused prefix; a changed one re-prefills from here.
volatile_parts: List[str] = [skills_prompt, *_memory_parts(agent)]
# Plugin sections are confined to one coarse anchor in the volatile tail so
# a resumed process can reconstruct the stable prefix without re-running plugins.
volatile_parts.extend(_plugin_section_blocks(_frozen_plugin_prompt_sections(agent), "after_memory"))
volatile_parts.append(_timestamp_line(agent))
# Keep the renderer-owned runtime anchor after all user/plugin prose so quoted
# host examples cannot shadow it during persisted-prompt validation.
if environment_hints:
# Embedder hints are prose too; reserve the delimiter for the renderer.
environment_hints = environment_hints.replace(_pb.RUNTIME_ENVIRONMENT_HEADING, "> " + _pb.RUNTIME_ENVIRONMENT_HEADING)
volatile_parts.append(f"{_pb.RUNTIME_ENVIRONMENT_HEADING}\n\n{environment_hints}\n\n{_pb.RUNTIME_ENVIRONMENT_END}")
return {"stable": _join_tier(stable_parts), "context": _join_tier(context_parts), "volatile": _join_tier(volatile_parts)}
def build_system_prompt(agent: Any, system_message: Optional[str] = None) -> str:
"""Assemble the full prompt; cached on ``agent._cached_system_prompt`` and
only rebuilt after compression. Tiers are ordered stable -> context ->
volatile so implicit longest-prefix caches keep the unchanged scaffold."""
parts = build_system_prompt_parts(agent, system_message=system_message)
agent._cached_system_prompt_static = parts["stable"]
# Surface context-file truncation warnings in chat, not only in logs.
for warning in drain_truncation_warnings():
agent._emit_status(warning)
return "\n\n".join(p for p in (parts["stable"], parts["context"], parts["volatile"]) if p)
def invalidate_system_prompt(agent: Any) -> None:
"""Force a rebuild on the next turn (after compression): reload memory from
disk and clear the frozen plugin snapshot (previous bytes stashed as the
fail-open fallback) so plugins re-render at the same boundary.
Called after context compression events. Also reloads memory from disk so the rebuilt prompt captures
any writes from this session, and clears the frozen plugin-section snapshot so plugins re-render at the
same boundary (maintainer-directed, #95681 arc): a plugin section is just another prompt block carrying
state — freezing it while memory, skills, and guidance refresh would recreate the stale-block disease
inside plugin-land. The previous bytes are stashed so a plugin whose render RAISES falls back to its
last good section instead of vanishing (fail-open guard, not a freeze).
"""
agent._cached_system_prompt = None
agent._cached_system_prompt_static = None
if hasattr(agent, "_plugin_system_prompt_sections_snapshot"):
agent._plugin_system_prompt_sections_previous = agent._plugin_system_prompt_sections_snapshot
del agent._plugin_system_prompt_sections_snapshot
if agent._memory_store:
agent._memory_store.load_from_disk()
def reconstruct_static_prefix(agent: Any, system_message: Optional[str] = None, *, log_label: str = "restore") -> None:
"""Reconstruct ``_cached_system_prompt_static`` for a stored prompt.
Only the full prompt is persisted, so restore / keep-prompt compression /
mid-turn failover to a cache-on provider must rebuild the stable tier to
regain the ``[static, volatile]`` layout. The rebuilt tier is used ONLY
when the stored prompt literally starts with it; otherwise static stays
None and the stored bytes are sent untouched. A failed rebuild is memoized
per stored prompt so the retry-loop hot path doesn't redo the file I/O."""
stored = getattr(agent, "_cached_system_prompt", None)
existing = getattr(agent, "_cached_system_prompt_static", None)
if (
not getattr(agent, "_use_prompt_caching", False)
or not isinstance(stored, str) or not stored
or (isinstance(existing, str) and existing and stored.startswith(existing))
or getattr(agent, "_static_rebuild_failed_for", None) == stored
):
return
try:
static = build_system_prompt_parts(agent, system_message=system_message)["stable"]
if static and stored.startswith(static):
agent._cached_system_prompt_static = static
agent._static_rebuild_failed_for = None
return
except Exception:
logger.debug("static system-prefix reconstruction failed on %s", log_label, exc_info=True)
agent._cached_system_prompt_static = None
agent._static_rebuild_failed_for = stored
def format_tools_for_system_message(agent: Any) -> str:
"""JSON tool definitions in the trajectory format."""
if not agent.tools:
return "[]"
return json.dumps([{"name": t["function"]["name"], "description": t["function"].get("description", ""),
"parameters": t["function"].get("parameters", {}),
"required": None} # Match the format in the example
for t in agent.tools], ensure_ascii=False)
__all__ = ["build_system_prompt_parts", "build_system_prompt", "invalidate_system_prompt",
"platform_hint", "restore_plugin_prompt_sections", "format_tools_for_system_message"]
# ---- BEGIN PLUGIN-COMPAT (revert-scheduled; see COMPAT_MANIFEST.md) ----
# Names external plugins imported from this module before the Sep 2026 decomposition.
# Internal code MUST NOT use these (scripts/check_compat_pointers.py fails CI if it does).
# The whole block is removed by reverting the commit that added it.
_PLUGIN_COMPAT_LAZY = {
'OPENAI_MODEL_EXECUTION_GUIDANCE': ('agent.prompt_builder', 'OPENAI_MODEL_EXECUTION_GUIDANCE'),
}
def __getattr__(name): # PEP 562 — lazy so no import cycles
target = _PLUGIN_COMPAT_LAZY.get(name)
if target is None:
raise AttributeError(f"module {__name__!r} has no attribute {name!r}")
import importlib
from hermes_cli.plugin_compat import warn_once
warn_once(__name__, name, *target)
return getattr(importlib.import_module(target[0]), target[1])
# ---- END PLUGIN-COMPAT ----