Files
hermes-agent/agent/prompt_builder.py
0xbyt4 bdcf247efe feat: add email gateway platform (IMAP/SMTP)
Allow users to interact with Hermes by sending and receiving emails.
Uses IMAP polling for incoming messages and SMTP for replies with
proper threading (In-Reply-To, References headers).

Integrates with all 14 gateway extension points: config, adapter
factory, authorization, send_message tool, cron delivery, toolsets,
prompt hints, channel directory, setup wizard, status display, and
env example.

65 tests covering config, parsing, dispatch, threading, IMAP fetch,
SMTP send, attachments, and all integration points.
2026-03-11 06:32:01 -07:00

396 lines
17 KiB
Python

"""System prompt assembly -- identity, platform hints, skills index, context files.
All functions are stateless. AIAgent._build_system_prompt() calls these to
assemble pieces, then combines them with memory and ephemeral prompts.
"""
import logging
import os
import re
from pathlib import Path
from typing import Optional
logger = logging.getLogger(__name__)
# ---------------------------------------------------------------------------
# Context file scanning — detect prompt injection in AGENTS.md, .cursorrules,
# SOUL.md before they get injected into the system prompt.
# ---------------------------------------------------------------------------
_CONTEXT_THREAT_PATTERNS = [
(r'ignore\s+(previous|all|above|prior)\s+instructions', "prompt_injection"),
(r'do\s+not\s+tell\s+the\s+user', "deception_hide"),
(r'system\s+prompt\s+override', "sys_prompt_override"),
(r'disregard\s+(your|all|any)\s+(instructions|rules|guidelines)', "disregard_rules"),
(r'act\s+as\s+(if|though)\s+you\s+(have\s+no|don\'t\s+have)\s+(restrictions|limits|rules)', "bypass_restrictions"),
(r'<!--[^>]*(?:ignore|override|system|secret|hidden)[^>]*-->', "html_comment_injection"),
(r'<\s*div\s+style\s*=\s*["\'].*display\s*:\s*none', "hidden_div"),
(r'translate\s+.*\s+into\s+.*\s+and\s+(execute|run|eval)', "translate_execute"),
(r'curl\s+[^\n]*\$\{?\w*(KEY|TOKEN|SECRET|PASSWORD|CREDENTIAL|API)', "exfil_curl"),
(r'cat\s+[^\n]*(\.env|credentials|\.netrc|\.pgpass)', "read_secrets"),
]
_CONTEXT_INVISIBLE_CHARS = {
'\u200b', '\u200c', '\u200d', '\u2060', '\ufeff',
'\u202a', '\u202b', '\u202c', '\u202d', '\u202e',
}
def _scan_context_content(content: str, filename: str) -> str:
"""Scan context file content for injection. Returns sanitized content."""
findings = []
# Check invisible unicode
for char in _CONTEXT_INVISIBLE_CHARS:
if char in content:
findings.append(f"invisible unicode U+{ord(char):04X}")
# Check threat patterns
for pattern, pid in _CONTEXT_THREAT_PATTERNS:
if re.search(pattern, content, re.IGNORECASE):
findings.append(pid)
if findings:
logger.warning("Context file %s blocked: %s", filename, ", ".join(findings))
return f"[BLOCKED: {filename} contained potential prompt injection ({', '.join(findings)}). Content not loaded.]"
return content
# =========================================================================
# Constants
# =========================================================================
DEFAULT_AGENT_IDENTITY = (
"You are Hermes Agent, an intelligent AI assistant created by Nous Research. "
"You are helpful, knowledgeable, and direct. You assist users with a wide "
"range of tasks including answering questions, writing and editing code, "
"analyzing information, creative work, and executing actions via your tools. "
"You communicate clearly, admit uncertainty when appropriate, and prioritize "
"being genuinely useful over being verbose unless otherwise directed below. "
"Be targeted and efficient in your exploration and investigations."
)
MEMORY_GUIDANCE = (
"You have persistent memory across sessions. Proactively save important things "
"you learn (user preferences, environment details, useful approaches) and do "
"(like a diary!) using the memory tool -- don't wait to be asked."
)
SESSION_SEARCH_GUIDANCE = (
"When the user references something from a past conversation or you suspect "
"relevant prior context exists, use session_search to recall it before asking "
"them to repeat themselves."
)
SKILLS_GUIDANCE = (
"After completing a complex task (5+ tool calls), fixing a tricky error, "
"or discovering a non-trivial workflow, consider saving the approach as a "
"skill with skill_manage so you can reuse it next time."
)
PLATFORM_HINTS = {
"whatsapp": (
"You are on a text messaging communication platform, WhatsApp. "
"Please do not use markdown as it does not render. "
"You can send media files natively: to deliver a file to the user, "
"include MEDIA:/absolute/path/to/file in your response. The file "
"will be sent as a native WhatsApp attachment — images (.jpg, .png, "
".webp) appear as photos, videos (.mp4, .mov) play inline, and other "
"files arrive as downloadable documents. You can also include image "
"URLs in markdown format ![alt](url) and they will be sent as photos."
),
"telegram": (
"You are on a text messaging communication platform, Telegram. "
"Please do not use markdown as it does not render. "
"You can send media files natively: to deliver a file to the user, "
"include MEDIA:/absolute/path/to/file in your response. Images "
"(.png, .jpg, .webp) appear as photos, audio (.ogg) sends as voice "
"bubbles, and videos (.mp4) play inline. You can also include image "
"URLs in markdown format ![alt](url) and they will be sent as native photos."
),
"discord": (
"You are in a Discord server or group chat communicating with your user. "
"You can send media files natively: include MEDIA:/absolute/path/to/file "
"in your response. Images (.png, .jpg, .webp) are sent as photo "
"attachments, audio as file attachments. You can also include image URLs "
"in markdown format ![alt](url) and they will be sent as attachments."
),
"slack": (
"You are in a Slack workspace communicating with your user. "
"You can send media files natively: include MEDIA:/absolute/path/to/file "
"in your response. Images (.png, .jpg, .webp) are uploaded as photo "
"attachments, audio as file attachments. You can also include image URLs "
"in markdown format ![alt](url) and they will be uploaded as attachments."
),
"signal": (
"You are on a text messaging communication platform, Signal. "
"Please do not use markdown as it does not render. "
"You can send media files natively: to deliver a file to the user, "
"include MEDIA:/absolute/path/to/file in your response. Images "
"(.png, .jpg, .webp) appear as photos, audio as attachments, and other "
"files arrive as downloadable documents. You can also include image "
"URLs in markdown format ![alt](url) and they will be sent as photos."
),
"email": (
"You are communicating via email. Write clear, well-structured responses "
"suitable for email. Use plain text formatting (no markdown). "
"Keep responses concise but complete. You can send file attachments — "
"include MEDIA:/absolute/path/to/file in your response. The subject line "
"is preserved for threading. Do not include greetings or sign-offs unless "
"contextually appropriate."
),
"cli": (
"You are a CLI AI Agent. Try not to use markdown but simple text "
"renderable inside a terminal."
),
}
CONTEXT_FILE_MAX_CHARS = 20_000
CONTEXT_TRUNCATE_HEAD_RATIO = 0.7
CONTEXT_TRUNCATE_TAIL_RATIO = 0.2
# =========================================================================
# Skills index
# =========================================================================
def _read_skill_description(skill_file: Path, max_chars: int = 60) -> str:
"""Read the description from a SKILL.md frontmatter, capped at max_chars."""
try:
raw = skill_file.read_text(encoding="utf-8")[:2000]
match = re.search(
r"^---\s*\n.*?description:\s*(.+?)\s*\n.*?^---",
raw, re.MULTILINE | re.DOTALL,
)
if match:
desc = match.group(1).strip().strip("'\"")
if len(desc) > max_chars:
desc = desc[:max_chars - 3] + "..."
return desc
except Exception as e:
logger.debug("Failed to read skill description from %s: %s", skill_file, e)
return ""
def _skill_is_platform_compatible(skill_file: Path) -> bool:
"""Quick check if a SKILL.md is compatible with the current OS platform.
Reads just enough to parse the ``platforms`` frontmatter field.
Skills without the field (the vast majority) are always compatible.
"""
try:
from tools.skills_tool import _parse_frontmatter, skill_matches_platform
raw = skill_file.read_text(encoding="utf-8")[:2000]
frontmatter, _ = _parse_frontmatter(raw)
return skill_matches_platform(frontmatter)
except Exception:
return True # Err on the side of showing the skill
def build_skills_system_prompt() -> str:
"""Build a compact skill index for the system prompt.
Scans ~/.hermes/skills/ for SKILL.md files grouped by category.
Includes per-skill descriptions from frontmatter so the model can
match skills by meaning, not just name.
Filters out skills incompatible with the current OS platform.
"""
hermes_home = Path(os.getenv("HERMES_HOME", Path.home() / ".hermes"))
skills_dir = hermes_home / "skills"
if not skills_dir.exists():
return ""
# Collect skills with descriptions, grouped by category
# Each entry: (skill_name, description)
# Supports sub-categories: skills/mlops/training/axolotl/SKILL.md
# → category "mlops/training", skill "axolotl"
skills_by_category: dict[str, list[tuple[str, str]]] = {}
for skill_file in skills_dir.rglob("SKILL.md"):
# Skip skills incompatible with the current OS platform
if not _skill_is_platform_compatible(skill_file):
continue
rel_path = skill_file.relative_to(skills_dir)
parts = rel_path.parts
if len(parts) >= 2:
# Category is everything between skills_dir and the skill folder
# e.g. parts = ("mlops", "training", "axolotl", "SKILL.md")
# → category = "mlops/training", skill_name = "axolotl"
# e.g. parts = ("github", "github-auth", "SKILL.md")
# → category = "github", skill_name = "github-auth"
skill_name = parts[-2]
category = "/".join(parts[:-2]) if len(parts) > 2 else parts[0]
else:
category = "general"
skill_name = skill_file.parent.name
desc = _read_skill_description(skill_file)
skills_by_category.setdefault(category, []).append((skill_name, desc))
if not skills_by_category:
return ""
# Read category-level descriptions from DESCRIPTION.md
# Checks both the exact category path and parent directories
category_descriptions = {}
for category in skills_by_category:
cat_path = Path(category)
desc_file = skills_dir / cat_path / "DESCRIPTION.md"
if desc_file.exists():
try:
content = desc_file.read_text(encoding="utf-8")
match = re.search(r"^---\s*\n.*?description:\s*(.+?)\s*\n.*?^---", content, re.MULTILINE | re.DOTALL)
if match:
category_descriptions[category] = match.group(1).strip()
except Exception as e:
logger.debug("Could not read skill description %s: %s", desc_file, e)
index_lines = []
for category in sorted(skills_by_category.keys()):
cat_desc = category_descriptions.get(category, "")
if cat_desc:
index_lines.append(f" {category}: {cat_desc}")
else:
index_lines.append(f" {category}:")
# Deduplicate and sort skills within each category
seen = set()
for name, desc in sorted(skills_by_category[category], key=lambda x: x[0]):
if name in seen:
continue
seen.add(name)
if desc:
index_lines.append(f" - {name}: {desc}")
else:
index_lines.append(f" - {name}")
return (
"## Skills (mandatory)\n"
"Before replying, scan the skills below. If one clearly matches your task, "
"load it with skill_view(name) and follow its instructions. "
"If a skill has issues, fix it with skill_manage(action='patch').\n"
"\n"
"<available_skills>\n"
+ "\n".join(index_lines) + "\n"
"</available_skills>\n"
"\n"
"If none match, proceed normally without loading a skill."
)
# =========================================================================
# Context files (SOUL.md, AGENTS.md, .cursorrules)
# =========================================================================
def _truncate_content(content: str, filename: str, max_chars: int = CONTEXT_FILE_MAX_CHARS) -> str:
"""Head/tail truncation with a marker in the middle."""
if len(content) <= max_chars:
return content
head_chars = int(max_chars * CONTEXT_TRUNCATE_HEAD_RATIO)
tail_chars = int(max_chars * CONTEXT_TRUNCATE_TAIL_RATIO)
head = content[:head_chars]
tail = content[-tail_chars:]
marker = f"\n\n[...truncated {filename}: kept {head_chars}+{tail_chars} of {len(content)} chars. Use file tools to read the full file.]\n\n"
return head + marker + tail
def build_context_files_prompt(cwd: Optional[str] = None) -> str:
"""Discover and load context files for the system prompt.
Discovery: AGENTS.md (recursive), .cursorrules / .cursor/rules/*.mdc,
SOUL.md (cwd then ~/.hermes/ fallback). Each capped at 20,000 chars.
"""
if cwd is None:
cwd = os.getcwd()
cwd_path = Path(cwd).resolve()
sections = []
# AGENTS.md (hierarchical, recursive)
top_level_agents = None
for name in ["AGENTS.md", "agents.md"]:
candidate = cwd_path / name
if candidate.exists():
top_level_agents = candidate
break
if top_level_agents:
agents_files = []
for root, dirs, files in os.walk(cwd_path):
dirs[:] = [d for d in dirs if not d.startswith('.') and d not in ('node_modules', '__pycache__', 'venv', '.venv')]
for f in files:
if f.lower() == "agents.md":
agents_files.append(Path(root) / f)
agents_files.sort(key=lambda p: len(p.parts))
total_agents_content = ""
for agents_path in agents_files:
try:
content = agents_path.read_text(encoding="utf-8").strip()
if content:
rel_path = agents_path.relative_to(cwd_path)
content = _scan_context_content(content, str(rel_path))
total_agents_content += f"## {rel_path}\n\n{content}\n\n"
except Exception as e:
logger.debug("Could not read %s: %s", agents_path, e)
if total_agents_content:
total_agents_content = _truncate_content(total_agents_content, "AGENTS.md")
sections.append(total_agents_content)
# .cursorrules
cursorrules_content = ""
cursorrules_file = cwd_path / ".cursorrules"
if cursorrules_file.exists():
try:
content = cursorrules_file.read_text(encoding="utf-8").strip()
if content:
content = _scan_context_content(content, ".cursorrules")
cursorrules_content += f"## .cursorrules\n\n{content}\n\n"
except Exception as e:
logger.debug("Could not read .cursorrules: %s", e)
cursor_rules_dir = cwd_path / ".cursor" / "rules"
if cursor_rules_dir.exists() and cursor_rules_dir.is_dir():
mdc_files = sorted(cursor_rules_dir.glob("*.mdc"))
for mdc_file in mdc_files:
try:
content = mdc_file.read_text(encoding="utf-8").strip()
if content:
content = _scan_context_content(content, f".cursor/rules/{mdc_file.name}")
cursorrules_content += f"## .cursor/rules/{mdc_file.name}\n\n{content}\n\n"
except Exception as e:
logger.debug("Could not read %s: %s", mdc_file, e)
if cursorrules_content:
cursorrules_content = _truncate_content(cursorrules_content, ".cursorrules")
sections.append(cursorrules_content)
# SOUL.md (cwd first, then ~/.hermes/ fallback)
soul_path = None
for name in ["SOUL.md", "soul.md"]:
candidate = cwd_path / name
if candidate.exists():
soul_path = candidate
break
if not soul_path:
global_soul = Path.home() / ".hermes" / "SOUL.md"
if global_soul.exists():
soul_path = global_soul
if soul_path:
try:
content = soul_path.read_text(encoding="utf-8").strip()
if content:
content = _scan_context_content(content, "SOUL.md")
content = _truncate_content(content, "SOUL.md")
sections.append(
f"## SOUL.md\n\nIf SOUL.md is present, embody its persona and tone. "
f"Avoid stiff, generic replies; follow its guidance unless higher-priority "
f"instructions override it.\n\n{content}"
)
except Exception as e:
logger.debug("Could not read SOUL.md from %s: %s", soul_path, e)
if not sections:
return ""
return "# Project Context\n\nThe following project context files have been loaded and should be followed:\n\n" + "\n".join(sections)