deadends.dev

Stop AI agents from repeating known failures - in code AND in the real world.
AI assistants reliably fumble two kinds of problems: known-failed code fixes, and
country-specific real-world rules they've never been exposed to in training.
deadends.dev now covers both:
- Code errors (2,089 entries, 51 domains): what NOT to try when an agent
hits
ModuleNotFoundError, CUDA OOM, CrashLoopBackOff, etc.
- Country-scoped dead ends (250+ entries across 52 countries): visa rules
(ETA/eVisitor, NZeTA, e-visas, arrival cards), banking requirements, legal red
lines (lèse-majesté, §86a, Article 301), cultural taboos (chopsticks in rice,
clock gifts in China, red-ink names in Korea), food safety (tap-water safety by
country), emergency numbers, driving norms (left-hand traffic), housing
contracts - all the friction where a plausible-sounding global answer is wrong
locally.
Why the expansion? Coding dead ends are largely solved by a good LLM.
Country-specific friction - Japanese hanko requirements, Schengen 90/180
math, Ramadan business hours, Saudi alcohol ban, Indian beef taboos - is
where generic AI advice breaks hardest. The codebase and schema are
identical; the env segment just carries a country code.
90% Precision@1 · 0.935 MRR · Data Quality Dashboard
Website: deadends.dev · MCP Server: Smithery · PyPI: deadends-dev · API: /api/v1/index.json
Repository: https://github.com/dbwls99706/deadends.dev
Why Use This?
| Without deadends.dev | With deadends.dev |
|---|
Agent tries sudo pip install → breaks system Python → wastes 3 retries | Agent sees "dead end: sudo pip - fails 70%" → skips it immediately |
| Agent tells user to tip 15% at a Tokyo restaurant | Agent knows tipping is refused in Japan (culture/tipping-refused/jp) |
| Agent drafts a Thai social post referencing King Rama X | Agent stops: Article 112 lèse-majesté risk (legal/lese-majeste-article-112/th) |
| Agent fixes error A, gets confused by error B | Agent knows "A leads to B 78% of the time" → handles both |
| Agent tells unmarried couple to kiss publicly in Dubai | Agent flags UAE public decency law (legal/unmarried-public-affection/ae) |
What makes this different from asking an LLM?
- Deterministic: Same query → same answer, every time. No hallucination.
- Country-scoped: ID format
{domain}/{slug}/{env} - env holds the country
code (kr, jp, us, de...) so the same taboo can be answered
differently for different jurisdictions.
- Primary-sourced: Every country canon cites government sites, embassies,
or verifiable reporting. No "based on general knowledge" answers.
- Community-validated: Fix success rates updated from real outcome reports.
- Sub-millisecond: Local regex matching, no API roundtrip.
현실적인 한계 (운영 관점)
- 모든 에러를 다 커버하지는 못합니다. 없는 케이스는 이슈/PR/
report_outcome로 빠르게 보완합니다.
- 설명의 깊이보다 실전 해결 우선(dead end/workaround 중심)으로 설계되어 있습니다.
- 신뢰성은 도메인/케이스마다 다를 수 있으므로, 고위험 변경은 공식 문서/벤더 가이드와 교차 검증을 권장합니다.
Quick Start (30 seconds)
pip install deadends-dev
deadends "CUDA error: out of memory"
MCP Server (Claude Desktop / Cursor)
Add to ~/.claude/claude_desktop_config.json:
{
"mcpServers": {
"deadend": {
"command": "python",
"args": ["-m", "mcp.server"],
"cwd": "/path/to/deadends.dev"
}
}
}
Or install via Smithery (no local setup):
npx -y @smithery/cli@latest install deadend/deadends-dev --client claude
MCP Unauthorized 빠른 해결 가이드 (사람용)
deadend: calling "initialize": sending "initialize": Unauthorized 에러가 보이면 아래를 순서대로 그대로 실행/확인하세요.
- 로컬 서버 모드인지, 원격(Smithery) 모드인지 하나만 사용
python -m mcp.server --help
- Claude Desktop 설정 파일 점검 (
cwd는 실제 경로여야 함)
cat ~/.claude/claude_desktop_config.json
- 로컬 서버 직접 실행 테스트
cd /path/to/deadends.dev
python -m mcp.server
- Smithery 모드라면 재설치(토큰/설정 꼬임 복구)
npx -y @smithery/cli@latest uninstall deadend/deadends-dev --client claude
npx -y @smithery/cli@latest install deadend/deadends-dev --client claude
- 마지막으로 Claude Desktop 완전 재시작
osascript -e 'quit app "Claude"'
open -a Claude
팁: Unauthorized는 보통 잘못된 cwd, 중복 서버 설정(로컬+원격 동시), 또는 만료된 인증 상태에서 발생합니다.
Antigravity (Google AI IDE)
Add as a remote MCP server - no authentication required:
{
"mcpServers": {
"deadend": {
"serverUrl": "https://deadends.dev/mcp",
"type": "http"
}
}
}
Note: Antigravity uses serverUrl (not url). If you get Unauthorized, remove any existing deadend entries from the MCP Store and re-add manually using the config above. See the Antigravity MCP auth guide for general troubleshooting.
Python SDK
from generator.lookup import lookup, batch_lookup, search
result = lookup("ModuleNotFoundError: No module named 'torch'")
for d in result["dead_ends"]:
print(f"AVOID: {d['action']} - fails {int(d['fail_rate']*100)}%")
for w in result["workarounds"]:
print(f"TRY: {w['action']} - works {int(w['success_rate']*100)}%")
results = batch_lookup(["error1", "error2", "error3"])
Example Response
## ModuleNotFoundError: No module named 'X' (Python 3.11+)
Resolvable: true | Fix rate: 0.88
### Dead Ends (DO NOT TRY):
- pip install X with system Python (fails 70%): venv not activated
### Workarounds (TRY THESE):
- Create venv, activate, then pip install (works 95%)
- Use python -m pip install instead of bare pip (works 90%)
| Tool | Description |
|---|
lookup_error | Match an error message against 2000+ known patterns |
get_error_detail | Full canon by ID |
list_error_domains | All 54 domains with counts |
search_errors | TF-IDF keyword search across all domains |
list_errors_by_domain | All errors in a domain |
list_errors_by_country | All country-scoped dead ends for an ISO alpha-2 code |
get_country_summary | Country-level summary (entries, fix rate, domain mix) |
batch_lookup | Look up multiple errors at once (max 10) |
get_domain_stats | Domain quality metrics and confidence levels |
get_error_chain | Traverse the error transition graph |
report_outcome | Report whether a workaround worked (feeds back into success rates) |
API Endpoints
Covered Domains (54)
Code error domains (51)
| Domain | Errors | Examples |
|---|
| Python | 88 | ModuleNotFoundError, TypeError, KeyError, MemoryError, RecursionError |
| Node | 70 | ERR_MODULE_NOT_FOUND, EACCES, EADDRINUSE, heap OOM, ERR_REQUIRE_ESM |
| Docker | 65 | no space left, exec format error, bind address in use, healthcheck |
| Kubernetes | 61 | CrashLoopBackOff, ImagePullBackOff, OOMKilled, RBAC forbidden, HPA |
| Git | 60 | failed to push, merge conflicts, detached HEAD, stash apply, tags |
| CUDA | 57 | OOM, device-side assert, NCCL, cuDNN, tensor device mismatch |
| Go | 54 | nil pointer, unused import, interface conversion, slice out of range |
| Java | 54 | NullPointerException, ClassNotFound, OutOfMemoryError, connection pool |
| Database | 52 | deadlock, connection pool, slow query, replication lag |
| AWS | 51 | AccessDenied, S3 NoSuchBucket, Lambda timeout, CloudFormation rollback |
| .NET | 50 | NullReferenceException, LINQ translation, DI circular, EF concurrency |
| ROS 2 | 50 | node spin, launch error, QoS mismatch, tf2 transform |
| TypeScript | 49 | TS2307, TS2322, TS2345, TS2532, TS7053 |
| Rust | 48 | E0382 borrow, E0308 mismatch, E0277 trait, E0106 lifetime |
| + 37 more domains | 40+ each | CI/CD, PHP, Terraform, Networking, Next.js, React, pip, Android, ... |
Country-scoped real-world domains (new, growing)
| Domain | Covers | Example dead ends |
|---|
visa | Pre-travel authorization, overstay, re-entry bans | ESTA 90-day rule (US), K-ETA (KR), ETIAS/EES (Schengen), Schengen 90/180 (DE) |
banking | Account opening, KYC, foreigner rules | ARC required (KR), residence card 6-month (JP), SSN/ITIN (US) |
emergency | Correct emergency numbers, transit | 112 not 911 (DE), 999/101/111 (UK) |
medical | Insurance, Rx import, coverage | Shaho/Kokuho (JP), NHIS 6-month (KR), EHIC ineligibility (DE), Adderall import ban (JP) |
legal | Criminal liability, contract norms | §86a Nazi symbols (DE), Article 112 (TH), Article 301 (TR), alcohol ban (SA), key money (JP) |
culture | Etiquette, taboos, social norms | Chopsticks in rice (JP), clock gifts (CN), Tiananmen silence, red ink names (KR), bonjour (FR) |
food-safety | Water, pathogens, religious taboos | Tap water (MX), fugu license (JP), beef in India, pork in Indonesia |
communication | Language register, terminology | Honorifics (KR), American War framing (VN), 'gringo' (MX), Cantonese vs Mandarin (HK) |
safety | Driving, public-safety norms | Left-side drive (JP), Autobahn rules (DE), horn-language (IN) |
Data Quality
All metrics are publicly available on the Data Quality Dashboard:
- 2,204 canon entries across 54 domains and 39+ countries
- Benchmark: 90% Precision@1, 95% Precision@3, 0.935 MRR (on code scenarios)
- Error transition graph: 4,330+ edges connecting related errors
- Community feedback loop:
report_outcome updates fix success rates from real usage
- Country canons: every entry cites primary gov/embassy/regulator sources,
reviewed by humans (
review_status: human_reviewed), no LLM bulk generation
Country coverage (52 countries as of v0.10)
kr · jp · us · de · uk · fr · it · es · nl · ch · pt ·
ie · at · be · se · no · dk · fi · pl · gr · cn · hk ·
tw · th · in · vn · id · sg · ph · my · pk · bd · sa ·
ae · tr · il · ru · br · mx · ar · cl · co · pe · au ·
nz · eg · ma · et · ng · ke · za · ca
See /country/ hub or
/api/v1/countries.json for the
authoritative list with counts.
See docs/country-canon-guide.md for the
authoring workflow, sourcing requirements, and confidence calibration.
Contributing
See CONTRIBUTING.md for full details.
Development
pip install -e ".[dev]"
python -m generator.pipeline
python -m generator.build_site
python -m generator.validate
python -m pytest tests/ -v
ruff check generator/ tests/
python benchmarks/run_benchmark.py
SEO 점검 가이드 (모든 페이지 공통)
아래 명령은 템플릿에 핵심 SEO 신호가 있는지 빠르게 점검합니다.
python - <<'PY'
from pathlib import Path
files=[
'generator/templates/index.html',
'generator/templates/domain.html',
'generator/templates/error_summary.html',
'generator/templates/page.html',
'generator/templates/search.html',
'generator/templates/dashboard.html',
]
required=[
'<title',
'meta name="description"',
'meta name="robots"',
'link rel="canonical"',
'meta property="og:title"',
'meta name="twitter:card"',
]
for f in files:
txt=Path(f).read_text()
missing=[r for r in required if r not in txt]
print(f'✅ {f}' if not missing else f'❌ {f} missing: {", ".join(missing)}')
PY
실제 빌드 결과물까지 확인하려면:
python -m generator.build_site
python -m http.server -d public 8080
그 후 브라우저에서 아래를 점검:
view-source:http://localhost:8080/search/
view-source:http://localhost:8080/dashboard/
- canonical / og / twitter / JSON-LD 유효성
Changelog
v0.10.0 - Country coverage expansion
- 250+ country canons across 52 countries (up from 56 across 20): emergency
numbers for nearly every supported country, modern visa gateways (ETA/eVisitor,
NZeTA, e-visas, digital arrival cards), medication-import rules, tap-water
safety, left-hand-traffic safety, and banking access - all primary-sourced and
human-reviewed
- By-destination cross-linking: country summary pages now link to other dead
ends for the same country across domains (a "More dead ends in {country}"
section), strengthening topical internal linking
- SEO: sitemap
<priority> weighted by page strength (country/high-evidence
pages ranked higher); JSON-LD omits empty dates
- Style: em-dash removed site-wide in favor of the hyphen
v0.9.0 - Country pivot
- New axis: country-scoped real-world dead ends alongside code errors
- 56+ country canons across 20+ countries - visa, banking, legal red
lines, cultural taboos, food safety, emergency numbers, driving norms
- 3 new domains:
visa, banking, emergency (plus extended use of
existing legal, culture, medical, communication, food-safety,
safety domains with country env segment)
- Per-country landing pages at
/country/{cc}/ (e.g.
/country/jp/)
generator.country_canon_template helper for authoring new country
canons with validated env-segment + audience + jurisdiction metadata
docs/country-canon-guide.md: sourcing standards (primary > embassy
reputable media), confidence calibration, slug/regex conventions
- Schema unchanged (backward-compatible enum extensions); existing 2,089
code canons preserved
v0.8.0
- Benchmark suite: 20 error scenarios, Precision@1=90%, MRR=0.935
- Data quality dashboard at
/dashboard/ - transparent metrics
- Outcome feedback loop:
report_outcome → aggregated stats → fix_success_rate updates
- Usage analytics: anonymous tool usage tracking (domain/match only, no PII)
- Community contribution: GitHub Issue templates for new errors and workaround reports
- TF-IDF search: improved relevance with smoothed IDF scoring
- Error transition graph: materialized graph with 4,330+ edges, hub node analysis
- 9 MCP tools (added
report_outcome)
v0.7.0
- Expanded to 2089 error entries across 51 domains (from 1028/20)
- Added 23 new domains
- Fixed 73 regex patterns that didn't match their own signatures
v0.5.0
page_url field added to index.json, errors.ndjson, and all SDK/MCP responses
- SEO fixes for canonical summary URLs
v0.4.0
- Initial public release with 1028 error entries across 20 domains
License
MIT (code) · CC BY 4.0 (data)
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