Replace blacklist approach with explicit whitelist for child process
environment variables to prevent secret exfiltration via creative naming.
Changes:
- tools/code_execution_tool.py: Implement _ALLOWED_ENV_VARS frozenset
- Only pass explicitly listed env vars to sandboxed child processes
- Drop all other variables silently to prevent credential theft
Fixes CWE-526: Exposure of Sensitive Information to an Unauthorized Actor
CVSS: 9.3 (Critical)
Refs: V-003 in SECURITY_AUDIT_REPORT.md
* feat: env var passthrough for skills and user config
Skills that declare required_environment_variables now have those vars
passed through to sandboxed execution environments (execute_code and
terminal). Previously, execute_code stripped all vars containing KEY,
TOKEN, SECRET, etc. and the terminal blocklist removed Hermes
infrastructure vars — both blocked skill-declared env vars.
Two passthrough sources:
1. Skill-scoped (automatic): when a skill is loaded via skill_view and
declares required_environment_variables, vars that are present in
the environment are registered in a session-scoped passthrough set.
2. Config-based (manual): terminal.env_passthrough in config.yaml lets
users explicitly allowlist vars for non-skill use cases.
Changes:
- New module: tools/env_passthrough.py — shared passthrough registry
- hermes_cli/config.py: add terminal.env_passthrough to DEFAULT_CONFIG
- tools/skills_tool.py: register available skill env vars on load
- tools/code_execution_tool.py: check passthrough before filtering
- tools/environments/local.py: check passthrough in _sanitize_subprocess_env
and _make_run_env
- 19 new tests covering all layers
* docs: add environment variable passthrough documentation
Document the env var passthrough feature across four docs pages:
- security.md: new 'Environment Variable Passthrough' section with
full explanation, comparison table, and security considerations
- code-execution.md: update security section, add passthrough subsection,
fix comparison table
- creating-skills.md: add tip about automatic sandbox passthrough
- skills.md: add note about passthrough after secure setup docs
Live-tested: launched interactive CLI, loaded a skill with
required_environment_variables, verified TEST_SKILL_SECRET_KEY was
accessible inside execute_code sandbox (value: passthrough-test-value-42).
Complete cleanup after dropping the mini-swe-agent submodule (PR #2804):
- Remove MSWEA_SILENT_STARTUP and MSWEA_GLOBAL_CONFIG_DIR env var
settings from cli.py, run_agent.py, hermes_cli/main.py, doctor.py
- Remove mini-swe-agent health check from hermes doctor
- Remove 'minisweagent' from logger suppression lists
- Remove litellm/typer/platformdirs from requirements.txt
- Remove mini-swe-agent install steps from install.ps1 (Windows)
- Remove mini-swe-agent install steps from website docs
- Update all stale comments/docstrings referencing mini-swe-agent
in terminal_tool.py, tools/__init__.py, code_execution_tool.py,
environments/README.md, environments/agent_loop.py
- Remove mini_swe_runner from pyproject.toml py-modules
(still exists as standalone script for RL training use)
- Shrink test_minisweagent_path.py to empty stub
The orphaned mini-swe-agent/ directory on disk needs manual removal:
rm -rf mini-swe-agent/
Root cause: terminal_tool, execute_code, and process_registry returned raw
subprocess output with ANSI escape sequences intact. The model saw these
in tool results and copied them into file writes.
Previous fix (PR #2532) stripped ANSI at the write point in file_tools.py,
but this was a band-aid — regex on file content risks corrupting legitimate
content, and doesn't prevent ANSI from wasting tokens in the model context.
Source-level fix:
- New tools/ansi_strip.py with comprehensive ECMA-48 regex covering CSI
(incl. private-mode, colon-separated, intermediate bytes), OSC (both
terminators), DCS/SOS/PM/APC strings, Fp/Fe/Fs/nF escapes, 8-bit C1
- terminal_tool.py: strip output before returning to model
- code_execution_tool.py: strip stdout/stderr before returning
- process_registry.py: strip output in poll/read_log/wait
- file_tools.py: remove _strip_ansi band-aid (no longer needed)
Verified: `ls --color=always` output returned as clean text to model,
file written from that output contains zero ESC bytes.
Two fixes:
1. Use a single open(os.devnull) handle for both stdout and stderr
suppression, preventing a file handle leak if the second open() fails.
2. Set server_sock = None after closing it in the try block to prevent
the finally block from closing it again (causing an OSError).
Closes#2136
Co-authored-by: dieutx <dangtc94@gmail.com>
* fix(tools): improve error logging in code_execution_tool
* fix: harden execute_code cleanup and reduce logging noise
Follow-up to cherry-picked PR #1588 (aydnOktay):
- Initialize server_sock = None before try block to prevent NameError
if exception occurs before socket creation (line 413 is inside the try)
- Guard server_sock.close() with None check
- Narrow cleanup exception handlers to OSError (the actual error type)
- Remove exc_info=True from cleanup debug logs — benign teardown
failures don't need stack traces, the message is sufficient
- Remove redundant try/except around shutil.rmtree(ignore_errors=True)
- Silence sock_path unlink with pass — expected when already cleaned up
---------
Co-authored-by: aydnOktay <xaydinoktay@gmail.com>
- Add 'emoji' field to ToolEntry and 'get_emoji()' to ToolRegistry
- Add emoji= to all 50+ registry.register() calls across tool files
- Add get_tool_emoji() helper in agent/display.py with 3-tier resolution:
skin override → registry default → hardcoded fallback
- Replace hardcoded emoji maps in run_agent.py, delegate_tool.py, and
gateway/run.py with centralized get_tool_emoji() calls
- Add 'tool_emojis' field to SkinConfig so skins can override per-tool
emojis (e.g. ares skin could use swords instead of wrenches)
- Add 11 tests (5 registry emoji, 6 display/skin integration)
- Update AGENTS.md skin docs table
Based on the approach from PR #1061 by ForgingAlex (emoji centralization
in registry). This salvage fixes several issues from the original:
- Does NOT split the cronjob tool (which would crash on missing schemas)
- Does NOT change image_generate toolset/requires_env/is_async
- Does NOT delete existing tests
- Completes the centralization (gateway/run.py was missed)
- Hooks into the skin system for full customizability
The execute_code sandbox spawns a child process with cwd set to a
temporary directory, but never adds the hermes-agent project root to
PYTHONPATH. This makes project-root modules like minisweagent_path
unreachable from sandboxed scripts, causing ImportError when the
agent runs self-diagnostic or analysis code via execute_code.
Fix by prepending the hermes-agent root directory to PYTHONPATH in
the child process environment.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Replaces head-only stdout capture with a two-buffer approach (40% head,
60% tail rolling window) so scripts that print() their final results
at the end never lose them. Adds truncation notice between sections.
Cherry-picked from PR #755, conflict resolved (test file additions).
3 new tests for short output, head+tail preservation, and notice format.
Follow-up to PR #705 (merged from 0xbyt4). Addresses several issues:
1. CONSECUTIVE-ONLY TRACKING: Redesigned the read/search tracker to only
warn/block on truly consecutive identical calls. Any other tool call
in between (write, patch, terminal, etc.) resets the counter via
notify_other_tool_call(), called from handle_function_call() in
model_tools.py. This prevents false blocks in read→edit→verify flows.
2. THRESHOLD ADJUSTMENT: Warn on 3rd consecutive (was 2nd), block on
4th+ consecutive (was 3rd+). Gives the model more room before
intervening.
3. TUPLE UNPACKING BUG: Fixed get_read_files_summary() which crashed on
search keys (5-tuple) when trying to unpack as 3-tuple. Now uses a
separate read_history set that only tracks file reads.
4. WEB_EXTRACT DOCSTRING: Reverted incorrect removal of 'title' from
web_extract return docs in code_execution_tool.py — the field IS
returned by web_tools.py.
5. TESTS: Rewrote test_read_loop_detection.py (35 tests) to cover
consecutive-only behavior, notify_other_tool_call, interleaved
read/search, and summary-unaffected-by-searches.
Completes the fix started in 8318a51 — handle_function_call() accepted
enabled_tools but run_agent.py never passed it. Now both call sites in
_execute_tool_calls() pass self.valid_tool_names, so each agent session
uses its own tool list instead of the process-global
_last_resolved_tool_names (which subagents can overwrite).
Also simplifies the redundant ternary in code_execution_tool.py:
sandbox_tools is already computed correctly (intersection with session
tools, or full SANDBOX_ALLOWED_TOOLS as fallback), so the conditional
was dead logic.
Inspired by PR #663 (JasonOA888). Closes#662.
Tests: 2857 passed.
build_execute_code_schema(set()) produced "from hermes_tools import , ..."
in the code property description — invalid Python syntax shown to the model.
This triggers when a user enables only the code_execution toolset without
any of the sandbox-allowed tools (e.g. `hermes tools code_execution`),
because SANDBOX_ALLOWED_TOOLS & {"execute_code"} = empty set.
Also adds 29 unit tests covering build_execute_code_schema, environment
variable filtering, execute_code edge cases, and interrupt handling.
PR #568 moved the close entirely to the finally block, but the success-path
close is needed to break the RPC thread out of accept() immediately. Without
it, rpc_thread.join(3) may block for up to 3 seconds if the child process
never connected. The finally-block close remains as a safety net for the
exception/error path (the actual fd leak fix).
Authored by alireza78a. Moves server_sock.close() into the finally block so
the socket fd is always cleaned up, even if an exception occurs between socket
creation and the success-path close.
Combine read/search loop detection with main's redact_sensitive_text
and truncation hint features. Add tracker reset to TestSearchHints
to prevent cross-test state leakage.
macOS sets TMPDIR to /var/folders/xx/.../T/ (~51 chars). Combined with
agent-browser session names, socket paths reach 121 chars — exceeding
the 104-byte macOS AF_UNIX limit. This causes 'Screenshot file was not
created' errors and silent browser_vision failures on macOS.
Fix: use /tmp/ on macOS (symlink to /private/tmp, sticky-bit protected).
On Linux, tempfile.gettempdir() already returns /tmp — no behavior change.
Changes in browser_tool.py:
- Add _socket_safe_tmpdir() helper — returns /tmp on macOS, gettempdir()
elsewhere
- Replace all 3 tempfile.gettempdir() calls for socket dirs
- Set mode=0o700 on socket dirs for privacy (was using default umask)
- Guard vision/text client init with try/except — a broken auxiliary
config no longer prevents the entire browser_tool module from importing
(which would disable all 10 browser tools, not just vision)
- Improve screenshot error messages with mode info and diagnostic hints
- Don't delete screenshots when LLM analysis fails — the capture was
valid, only the vision API call failed. Screenshots are still cleaned
up by the existing 24-hour _cleanup_old_screenshots mechanism.
Changes in code_execution_tool.py:
- Same /tmp fix for RPC socket path (was 103 chars on macOS — one char
from the 104-byte limit)
- Block file reads after 3+ re-reads of same region (no content returned)
- Track search_files calls and block repeated identical searches
- Filter completed/cancelled todos from post-compression injection
to prevent agent from re-doing finished work
- Add 10 new tests covering all three fixes
The web_extract_tool was stripping the 'url' key during its output
trimming step, but documentation in 3 places claimed it was present.
This caused KeyError when accessing result['url'] in execute_code
scripts, especially when extracting from multiple URLs.
Changes:
- web_tools.py: Add 'url' back to trimmed_results output
- code_execution_tool.py: Add 'title' to _TOOL_STUBS docstring and
_TOOL_DOC_LINES so docs match actual {url, title, content, error}
response format
Authored by areu01or00. Adds timezone support via hermes_time.now() helper
with IANA timezone resolution (HERMES_TIMEZONE env → config.yaml → server-local).
Updates system prompt timestamp, cron scheduling, and execute_code sandbox TZ
injection. Includes config migration (v4→v5) and comprehensive test coverage.
When a user disables the web toolset via 'hermes tools', the execute_code
schema description still hardcoded web_search/web_extract as available,
causing the model to keep trying to use them. Similarly, delegate_task
always defaulted to ['terminal', 'file', 'web'] for subagents regardless
of the parent's config.
Changes:
- execute_code schema is now built dynamically via build_execute_code_schema()
based on which sandbox tools are actually enabled
- model_tools.py rebuilds the execute_code schema at definition time using
the intersection of sandbox-allowed and session-enabled tools
- delegate_task now inherits the parent agent's enabled_toolsets instead of
hardcoding DEFAULT_TOOLSETS when no explicit toolsets are specified
- delegate_task description updated to say 'inherits your enabled toolsets'
Reported by kotyKD on Discord.
The _TOOL_STUBS dict in code_execution_tool.py was out of sync with the
actual tool schemas, causing TypeErrors when the LLM used parameters it
sees in its system prompt but the sandbox stubs didn't accept:
search_files:
- Added missing params: context, offset, output_mode
- Fixed target default: 'grep' → 'content' (old value was obsolete)
patch:
- Added missing params: mode, patch (V4A multi-file patch support)
Also added 4 drift-detection tests (TestStubSchemaDrift) that will
catch future divergence between stubs and real schemas:
- test_stubs_cover_all_schema_params: every schema param in stub
- test_stubs_pass_all_params_to_rpc: every stub param sent over RPC
- test_search_files_target_uses_current_values: no obsolete values
- test_generated_module_accepts_all_params: generated code compiles
All 28 tests pass.
The execute_code sandbox generates a hermes_tools.py stub module for LLM
scripts. Three common failure modes keep tripping up scripts:
1. json.loads(strict=True) rejects control chars in terminal() output
(e.g., GitHub issue bodies with literal tabs/newlines)
2. Shell backtick/quote interpretation when interpolating dynamic content
into terminal() commands (markdown with backticks gets eaten by bash)
3. No retry logic for transient network failures (API timeouts, rate limits)
Adds three convenience helpers to the generated hermes_tools module:
- json_parse(text) — json.loads with strict=False for tolerant parsing
- shell_quote(s) — shlex.quote() for safe shell interpolation
- retry(fn, max_attempts=3, delay=2) — exponential backoff wrapper
Also updates the EXECUTE_CODE_SCHEMA description to document these helpers
so LLMs know they're available without importing anything extra.
Includes 7 new tests (unit + integration) covering all three helpers.
os.setsid, os.killpg, and os.getpgid do not exist on Windows and raise
AttributeError on import or first call. This breaks the terminal tool,
code execution sandbox, process registry, and WhatsApp bridge on Windows.
Added _IS_WINDOWS platform guard in all four affected files, following
the pattern documented in CONTRIBUTING.md. On Windows, preexec_fn is
set to None and process termination falls back to proc.terminate() /
proc.kill() instead of process group signals.
Files changed:
- tools/environments/local.py (3 call sites)
- tools/process_registry.py (2 call sites)
- tools/code_execution_tool.py (3 call sites)
- gateway/platforms/whatsapp.py (3 call sites)
- Eliminated the temporary debug logging in the `execute_code` function that tracked enabled and sandbox tools, streamlining the code and reducing clutter.
- Modified the `_wrap` function to append a failure suffix without applying red coloring, simplifying the failure message format.
- Introduced temporary debug logging in the `execute_code` function to track enabled and sandbox tools, aiding in troubleshooting.
- Updated various modules including cli.py, run_agent.py, gateway, and tools to replace silent exception handling with structured logging.
- Improved error messages to provide more context, aiding in debugging and monitoring.
- Ensured consistent logging practices throughout the codebase, enhancing traceability and maintainability.
- Revised descriptions for various tools in model_tools.py, browser_tool.py, code_execution_tool.py, delegate_tool.py, and terminal_tool.py to enhance clarity and reduce verbosity.
- Improved consistency in terminology and formatting across tool descriptions, ensuring users have a clearer understanding of tool functionalities and usage.
- Changed the target parameter from "content" and "files" to "grep" and "find" to better represent their functionality.
- Revised descriptions in the tool definitions and execution code schema to enhance understanding of search modes and output formats.
- Ensured consistency in the handling of search operations across the codebase.
- Updated the tool name from "search" to "search_files" across multiple files to better reflect its functionality.
- Adjusted related documentation and descriptions to ensure clarity in usage and expected behavior.
- Enhanced the toolset definitions and mappings to incorporate the new naming convention, improving overall consistency in the codebase.
- Updated the default timeout for sandbox script execution from 120 seconds to 300 seconds (5 minutes) to allow longer-running scripts.
- Enhanced comments in the code execution tool to clarify the timeout duration.
- Suppressed stdout and stderr output from internal tool handlers during execution to prevent clutter in the CLI interface.
- Revised docstrings for `web_search` and `web_extract` functions to clarify return types and structure.
- Updated the execution code schema documentation to reflect changes in the output format for both tools, ensuring consistency and improved understanding for users.
- Introduced a new `execute_code` tool that allows the agent to run Python scripts that call Hermes tools via RPC, reducing the number of round trips required for tool interactions.
- Added configuration options for timeout and maximum tool calls in the sandbox environment.
- Updated the toolset definitions to include the new code execution capabilities, ensuring integration across platforms.
- Implemented comprehensive tests for the code execution sandbox, covering various scenarios including tool call limits and error handling.
- Enhanced the CLI and documentation to reflect the new functionality, providing users with clear guidance on using the code execution tool.
