Production mining (state.db, 28.5k read_file calls in the recent
window) shows 74.3% of reads truncated — nearly all by the 500-line
default, not the char budget (22,443 line-limit vs 13 char-budget
truncations). That churn produced 12,229 redundant re-reads, and after
a truncated result the most common next move was fleeing to terminal
cat/sed (4,608 times) — the pagination contract was not trusted.
Median truncated file is 2,422 total lines, so a 2000-line default
makes 44% of today's truncated first-reads complete in one call while
the unchanged ~100K-char budget still caps worst-case result size
(same ceiling as before: 500 lines x 2000-char line cap = the same
100K). Schema max was already 2000.
Touchpoints: DEFAULT_READ_LIMIT + both read_file signatures
(file_operations.py), read_file_tool + schema text (file_tools.py),
execute_code sandbox stub docs (code_execution_tool.py), 3 tests
pinning the old default.
Review follow-ups on the #25387 salvage:
1. CRITICAL: a cached miss survived out-of-band file creation (terminal
command, external process) for the full 60s TTL — breaking the common
agent pattern 'check for file -> create it -> read it' (live-repro'd).
Serve-side existence guard: one ~free stat before serving a cached
miss; if the path now exists the entry is evicted and the real read
runs. Also fixes the search-root variant (write under a cached-missing
directory). Both mutation-checked.
2. notify_other_tool_call now clears the task's not_found entries too
(belt: the dispatcher calls it for every non-read tool).
3. Tracking parity: the record sites no longer early-return. On upstream,
error results flow through consecutive-loop detection and dedup
bookkeeping; short-circuiting skipped that and broke
TestDedupInvalidationTaskResolution when preceded by
TestSilentFileMisplacementE2E (bisected: the early return at the
read record site was the trigger). Recording is now
side-effect-identical to upstream; serving from the cache remains the
optimization. Also reuse the already-computed _resolved instead of
resolving a second time.
When read_file or search hits a non-existent path, ShellFileOperations
spawns a subprocess to stat the path and another to walk the parent
directory for "did you mean..." suggestions. A typo'd path retried 13
times (observed in the wild) costs 26 subprocess invocations + 13 ls
walks for a result we already know.
Add a per-task negative-result cache keyed by (op, resolved_path) with
a 60s TTL and a hard cap of 500 entries. On hit, return the cached
error JSON immediately and skip the subprocess + suggestion walk.
The cache is namespaced by operation ("read" vs "search") because the
two callers return different error JSON shapes ("File not found:" vs
"Path not found:"). Eviction:
* TTL (60s) — short, so a path that appears later isn't masked.
* write_file / patch on the same path — _invalidate_dedup_for_path
now also drops the negative-cache entry so a freshly-written file
is read from disk on the next call instead of returning a stale
"not found" stub.
Tests in tests/tools/test_file_tools.py cover:
* read cache hit skips the subprocess on retry
* cache is per-task (no cross-task pollution)
* successful reads do not poison the cache
* search cache hit skips the subprocess on retry
* read and search caches are namespaced (different error shapes)
* write_file invalidates the read negative cache
* TTL expiry evicts stale entries
Three lower-severity core-tool robustness fixes from a targeted audit, each
reproduced live:
1. terminal_tool did not validate non-positive timeouts. 'timeout or default'
silently coerced 0 to the config default (0 can't mean 'no timeout'), and a
negative value is truthy so it flowed into 'deadline = now + timeout' and
fired an immediate '-Ns' timeout. Reject timeout <= 0 with a clear message.
2. fuzzy_find_and_replace accepted a whitespace-only old_string, which matches
trivially (blank line / run of spaces) and mass-replaces under replace_all
or raises an opaque ambiguity error. Reject it alongside the empty check.
3. The '/private/var/' sensitive-path prefix over-blocked ALL macOS temp-file
writes: , /tmp, and /var/folders realpath into /private/var/folders
on macOS (and paths are resolved through symlinks), and /private/var/tmp is
a normal temp dir. Narrowed to the genuinely-sensitive subtrees
(/private/var/db, /private/var/root); /etc and /private/etc stay blocked.
All verified with sabotage-checked regression tests. 85 terminal/fuzzy/file
tests pass; normal timeouts, legit replacements, and /var + /boot + /etc
blocking are unaffected.
Two independent HIGH-severity correctness bugs found in a core-tools audit,
each reproduced live against current main:
1. Read-dedup was never evicted after a write on non-default tasks.
_invalidate_dedup_for_path looked up the read-tracker under the correct
task_id but resolved the path with _resolve_path(filepath) — which
DEFAULTS task_id='default'. The dedup cache is keyed by the task-resolved
absolute path, so for any task whose workspace cwd differs from the process
cwd (every -w worktree / Desktop / ACP session using relative paths) the
computed key never matched and the stale entry was never removed. A
read_file after a write_file/patch could then return the OLD content stub
when mtime coincided. Fix: pass task_id through.
2. A per-command workdir override permanently hijacked the session cwd.
The post-command dual-write unconditionally recorded env.cwd (stamped to
the transient workdir) into the durable session-cwd store, so every later
command that omitted workdir inherited the one-off directory — contradicting
the documented 'Working directory for this command' contract. Fix: skip the
session-cwd record when workdir was explicitly supplied.
Both verified with sabotage-checked regression tests (fail without the fix).
Second, deeper pass over tools/gateway/hermes_cli plus first pass over
the trees wave 1 missed (acp, acp_adapter, skills, computer_use, docker,
dashboard, conformance, monitoring, secret_sources, hermes_state,
providers). Same rubric as wave 1 (AGENTS.md test policy); security,
alternation/caching invariants, issue-number regressions, and E2E kept.
Real test-quality fixes found and rooted out along the way:
- tests/tools/test_command_guards.py made real auxiliary-LLM HTTPS calls
(DEFAULT_CONFIG smart-approval leaked in) — pinned approval
mode=manual via autouse fixture: 17.4s → 0.4s.
- test_model_switch_custom_providers.py / test_user_providers_model_switch.py
silently probed live provider catalogs (~2s/test) — stubbed
cached_provider_model_ids/provider_model_ids/fetch_api_models.
- test_telegram_noise_filter.py: 15-platform copy-paste matrix over
shared gateway.run logic → 3 representative platforms (55s → 3.9s).
- test_gateway_shutdown.py: stop()'s 5s interrupt-deadline loop spun on
MagicMock agents — interrupt.side_effect now clears _running_agents
(22s → 1.0s).
- test_gateway_inactivity_timeout.py poll-harness timings shrunk 3-5x
(24s → 1.1s); test_mcp_stability.py backoff/SIGTERM-grace sleeps
patched (15.4s → 2.5s); test_async_delegation.py negative-drain wait
5s → 0.5s.
- test_telegram_init_deadline.py: loop-block margin restored to 1.0s
with rationale comment — the watchdog-dump assertion needs the loop
blocked well past deadline+grace under parallel load (flaked once in
the 40-worker verification run at a 0.2s margin).
Verification: full hermetic suite via scripts/run_tests.sh —
2,438 files, 21,718 tests passed, 0 failed, 293.9s wall.
Suite totals vs original baseline: 46,820 → 19,757 test functions
(−57.8%), wall 583.5s → 293.9s (−50%), subprocess CPU 13,564s → 11,623s.
The per-session record store is now the ONLY cwd mechanism. Deleted:
- env.cwd_owner stamping + prev_owner threading (terminal_tool): the
shared env no longer carries ownership metadata at all
- _resolve_command_cwd's env/prev_owner params: resolution is
workdir > session record > config/override default
- file_tools._live_cwd_if_owned + _get_live_tracking_cwd: path
resolution never consults the shared env's live cwd
- file_tools._last_known_cwd + _remember_last_known_cwd +
_last_known_cwd_for: the #26211 preserved-anchor registry is
subsumed by the session record, which never lived on the env and
therefore cannot be lost to env cleanup. The _get_file_ops
stale-cache rescue now writes the record instead.
- env recreation (both _get_file_ops and terminal_tool) seeds the
fresh env from override > session record > config
Why no transition fallback: the legacy state was process-local and
in-memory exactly like the record store — after a restart both start
empty, and within a running process every legacy write site has been
dual-writing the record since step 1. There is no populated-legacy/
empty-record state to fall back for.
Tests updated to drive the record store instead of the deleted
mechanism; the cross-session isolation suite now asserts the same
behavior contracts (no leak, cd isolation, #26211 persistence)
against the new architecture, plus a new "session C inherits nothing"
case that the old ownership guard could not express.
Git Bash hands file tools paths like /c/Users/... which Path() on native
Windows treats as relative \\c\\Users\\... under the process cwd. Reuse
local._msys_to_windows_path (extended for /cygdrive and /mnt drive forms)
in _resolve_path_for_task / _resolve_base_dir so read/write/search land on
the real drive. Container/WSL Linux paths are left untouched.
Salvages #50488 (drops unrelated desktop artifact commit); tests adapted
from #46995.
Co-authored-by: Jeff Watts <186512915+lEWFkRAD@users.noreply.github.com>
Co-authored-by: LeonSGP43 <cine.dreamer.one@gmail.com>
patch_tool extracts V4A patch paths so _check_sensitive_path can refuse
writes to /etc/*, /boot/*, etc. before they reach the low-level file ops.
The extraction regex had two gaps:
1. `*** Move File: src -> dst` was never extracted (regex only matched
Update/Add/Delete), so a Move targeting /etc/crontab skipped the
pre-check and fell back on the narrower file_operations deny list.
2. The regex required `\\s+` after `***` but patch_parser uses `\\s*`, so
`***Update File: /etc/hosts` (no space) parsed + applied while
skipping the check.
Loosen the leading whitespace to \\s* and add a Move regex that checks
both endpoints. Move endpoints also run through the same '..' traversal
rejection as the other V4A headers (closes the sibling gap on current
main, which gained that traversal guard after this PR was opened).
Belt-and-suspenders on top of the cherry-picked cwd-preservation fix:
- Proactively mirror every live terminal cwd into _last_known_cwd on each
successful read, so the durable anchor survives even when the cleanup
thread pops both _file_ops_cache and _active_environments before
_get_file_ops' stale-cache save branch can fire.
- Fall back to _last_known_cwd in _authoritative_workspace_root. write_file_tool
resolves the path (via _resolve_path_for_task) BEFORE _get_file_ops rebuilds
the env, so restoring only the rebuilt env's cwd was insufficient — the
resolution that decides where the file lands runs first. This closes that gap.
The local env's persisted _cwd_file can't serve this role: it's keyed by a
random per-session uuid and deleted on cleanup (the same cleanup that triggers
the bug). The in-memory _last_known_cwd registry is the durable anchor instead.
Adds a real-IO E2E regression (TestSilentFileMisplacementE2E) exercising the
actual write_file_tool path after env cleanup.
Root cause: when the terminal environment (`_active_environments` entry) is
cleaned up and re-created during a long conversation, the new environment
always starts with the default config CWD (typically `~/.hermes/hermes-agent`)
instead of preserving the user's last-known working directory. Subsequent
relative-path writes (`write_file`, `execute_code`, shell commands) silently
land in the default CWD, making files appear to be "created but absent."
Fix: add `_last_known_cwd` dict that preserves the old environment's CWD
before the stale cache entry is invalidated. When a new environment is
created for the same task_id, we check `_last_known_cwd` first and use the
preserved CWD instead of the config default.
Changes:
- tools/file_tools.py: add `_last_known_cwd` dict, save CWD before stale
cache invalidation, restore CWD on env recreation
- tests/tools/test_file_tools.py: add `TestLastKnownCwd` with 2 tests
verifying CWD preservation and fallback behavior
Fixes#26211
Remove unused imports (F401) and duplicate/shadowed import
redefinitions (F811) across the codebase using ruff's safe
autofixes. No behavioral changes -- imports only.
- ~1400 safe autofixes applied across 644 files (net -1072 lines)
- __init__.py re-exports preserved (excluded from F401 removal so
public re-export surfaces stay intact)
- Re-exports that are imported or monkeypatched by tests but look
unused in their defining module are kept with explicit # noqa:
F401 (gateway/run.py load_dotenv; run_agent re-exports from
agent.message_sanitization, agent.context_compressor,
agent.retry_utils, agent.prompt_builder, agent.process_bootstrap,
agent.codex_responses_adapter)
- Unsafe F841 (unused-variable) fixes deliberately skipped -- those
can change behavior when the RHS has side effects
- ruff lints remain disabled in pyproject.toml (only PLW1514 is
selected); this is a one-time cleanup, not a config change
Verification:
- python -m compileall: clean
- pytest --collect-only: all 27161 tests collect (zero import errors)
- core entry points import clean (run_agent, model_tools, cli,
toolsets, hermes_state, batch_runner, gateway)
- static scan: every name any test imports directly from an edited
module still resolves
V4A patch '*** Update File:', '*** Add File:', '*** Delete File:' headers
come from patch CONTENT, not the explicit `path=` argument. That makes
them attacker-influenceable through skill content, web extract output,
prompt injection, and other surfaces the agent processes. Headers like
'*** Update File: ../../../etc/shadow' would resolve relative to the
agent's cwd; in deployment configurations where that cwd is deep enough
to land outside Hermes' protected paths, the write could land somewhere
the agent operator did not intend.
Reject any V4A header containing a '..' path component before applying
the patch. The explicit `path=` argument on patch_tool is UNCHANGED —
the agent legitimately uses '..' there (e.g. `patch path='../other_module/x.py'`
from a worktree dir is normal cross-module editing).
Regression tests: V4A Update header with traversal rejected, V4A Add
header with traversal rejected, patch_v4a never invoked when rejection
fires.
Salvaged from PR #29395 by @waefrebeorn. The original PR added
has_traversal_component as a blanket reject on read_file_tool,
write_file_tool, patch_tool's explicit path, and search_tool — that
would break legitimate agent operation where '..' is normal. Also
dropped the over-eager skills_guard pattern additions
(pickle.loads/marshal.loads/ctypes.CDLL/importlib at high/critical
severity would false-positive on legit data-science and FFI skills).
Co-authored-by: teknium1 <127238744+teknium1@users.noreply.github.com>
Teknium: don't need 9 tests. Keep one invariant for 'per-mode required
params are documented in both description layers' and one that pins
required=[mode] with no anyOf/oneOf (prevents re-introducing the bug).
Models that enforce required-only constraints (e.g. kimi-k2.x) were
omitting old_string/new_string for replace mode and patch for patch mode
because the schema only declared required: ["mode"].
Add explicit "REQUIRED when mode='X'" markers to each conditionally-required
property description and a top-level "REQUIRED PARAMETERS: ..." summary for
each mode. Avoids anyOf/oneOf which break Anthropic, Fireworks, and
Kimi/Moonshot providers. Add TestPatchSchemaShape to lock the shape.
Fixes#15524
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Under context pressure, frontier models sometimes emit tool calls with
required fields dropped. Previously _handle_write_file() used
args.get('content', '') which substituted an empty string for the missing
key, returned success with bytes_written=0, and created a zero-byte file
on disk. The model had no way to detect the failure.
Changes:
- Reject calls where 'path' is absent or not a non-empty string
- Reject calls where 'content' key is entirely absent (key-presence check,
not truthiness) — distinguishing a legitimately empty file from a dropped arg
- Reject calls where 'content' is a non-string type
- All error messages include guidance to re-emit the tool call or switch
to execute_code with hermes_tools.write_file() for large payloads
- Explicit empty string content (file truncation) continues to work
Regression tests added for all four cases: missing path, missing content,
explicit-empty content, and wrong content type.
Fixes#19096
Make the main-branch test suite pass again. Most failures were tests
still asserting old shapes after recent refactors; two were real source
bugs.
Source fixes:
- tools/mcp_tool.py: _kill_orphaned_mcp_children() slept 2s on every
shutdown even when no tracked PIDs existed, making test_shutdown_is_parallel
measure ~3s for 3 parallel 1s shutdowns. Early-return when pids is empty.
- hermes_cli/tips.py: tip 105 was 157 chars; corpus max is 150.
Test fixes (mostly stale mock targets / missing fixture fields):
- test_zombie_process_cleanup, test_agent_cache: patch run_agent.cleanup_vm
(the local name bound at import), not tools.terminal_tool.cleanup_vm.
- test_browser_camofox: patch tools.browser_camofox.load_config, not
hermes_cli.config.load_config (the source module, not the resolved one).
- test_flush_memories_codex._chat_response_with_memory_call: add
finish_reason, tool_call.id, tool_call.type so the chat_completions
transport normalizer doesn't AttributeError.
- test_concurrent_interrupt: polling_tool signature now accepts
messages= kwarg that _invoke_tool() passes through.
- test_minimax_provider: add _fallback_chain=[] to the __new__'d agent
so switch_model() doesn't AttributeError.
- test_skills_config: SKILLS_DIR MagicMock + .rglob stopped working
after the scanner switched to agent.skill_utils.iter_skill_index_files
(os.walk-based). Point SKILLS_DIR at a real tmp_path and patch
agent.skill_utils.get_external_skills_dirs.
- test_browser_cdp_tool: browser_cdp toolset was intentionally split into
'browser-cdp' (commit 96b0f3700) so its stricter check_fn doesn't gate
the whole browser toolset; test now expects 'browser-cdp'.
- test_registry: add tools.browser_dialog_tool to the expected
builtin-discovery set (PR #14540 added it).
- test_file_tools TestPatchHints: patch_tool surfaces hints as a '_hint'
key on the JSON payload, not inline '[Hint: ...' text.
- test_write_deny test_hermes_env: resolve .env via get_hermes_home() so
the path matches the profile-aware denylist under hermetic HERMES_HOME.
- test_checkpoint_manager test_falls_back_to_parent: guard the walk-up
so a stray /tmp/pyproject.toml on the host doesn't pick up /tmp as the
project root.
- test_quick_commands: set cli.session_id in the __new__'d CLI so the
alias-args path doesn't trip AttributeError when fuzzy-matching leaks
a skill command across xdist test distribution.
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.
- treat git diff --cached --quiet rc=1 as an expected checkpoint state
instead of logging it as an error
- downgrade expected write PermissionError/EROFS/EACCES failures out of
error logging while keeping unexpected exceptions at error level
- add regression tests for both logging behaviors
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.
Terminal output was already redacted via redact_sensitive_text() but
read_file and search_files returned raw content. Now both tools
redact secrets before returning results to the LLM.
Based on PR #372 by @teyrebaz33 (closes#363) — applied manually
due to branch conflicts with the current codebase.
Add contextual [Hint: ...] suffixes to tool results where they save
real iterations:
- patch (no match): suggests read_file/search_files to verify content
before retrying — addresses the common pattern where the agent retries
with stale old_string instead of re-reading the file.
- search_files (truncated): provides explicit next offset and suggests
narrowing the search — clearer than relying on total_count inference.
Other hints proposed in #722 (terminal, web_search, web_extract,
browser_snapshot, search zero-results, search content-matches) were
evaluated and found to be low-value: either already covered by existing
mechanisms (read_file pagination, similar-files, schema descriptions)
or guidance the agent already follows from its own reasoning.
5 new tests covering hint presence/absence for both tools.
- Renamed test method for clarity and added comprehensive tests for `SessionSource` including handling of numeric `chat_id`, missing optional fields, and invalid platforms.
- Introduced tests for session source descriptions based on chat types and names, ensuring accurate representation in prompts.
- Improved file tools tests by validating schema structures, ensuring no duplicate model IDs, and enhancing error handling in file operations.
Teknium
kshitij
Kent
ethernet
Brooklyn Nicholson
0xbyt4
zccyman
Brandon Zarnitz
sbw2025
waefrebeorn
briandevans
Bartok9
Yukipukii1
Teknium