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deadends.dev

by dbwls99706version 0.9.0i★ –iComputer or cloud
Registry namedev.deadends/deadends-dev

Install

Overview

Description from the maker (original English)

Structured failure knowledge for AI agents — dead ends, workarounds, error chains

PopNx MCP’s three pillars

These three are never merged into one score: opinions, measurements and popularity are different things.

What you can do with it

We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.

Install

Pick the AI app you use, then copy the settings.

Before you install

  • Basic checks: 1 of 1 passed
  • Runs on the maker’s server: what you ask it goes through their server.
  • The registry lists no key to fill in.

You need

  • Runs in the cloudNothing to install; it connects over the internet
  • PyPIPython’s uv installed (for the uvx command)

Which app do you use?

Pick your app above. We remember it, so next time the button says “Install in …”.

Works in Claude on the web, desktop and mobile:

  1. Open Settings → Connectors
  2. Press Add custom connector
  3. Paste the address below and press Add
  4. If it asks you to sign in, sign in with the maker
SettingsConnectors1+ Add2https://…3
https://deadends.dev/mcp

Or run it on your computer

Open Claude Desktop → Settings → Developer → Edit Config, and paste this into claude_desktop_config.json

{
  "mcpServers": {
    "deadends-dev": {
      "command": "uvx",
      "args": [
        "deadends-dev"
      ]
    }
  }
}

Run this in your terminal

claude mcp add --transport http deadends-dev https://deadends.dev/mcp

Or run it on your computer

claude mcp add deadends-dev -- uvx deadends-dev

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "deadends-dev": {
      "url": "https://deadends.dev/mcp"
    }
  }
}

Or run it on your computer

Open in Cursor

Or copy the settings yourself

Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json

{
  "mcpServers": {
    "deadends-dev": {
      "command": "uvx",
      "args": [
        "deadends-dev"
      ]
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "deadends-dev": {
      "type": "http",
      "url": "https://deadends.dev/mcp"
    }
  }
}

Or run it on your computer

Open in VS Code

Or copy the settings yourself

Paste into .vscode/mcp.json in your project

{
  "servers": {
    "deadends-dev": {
      "type": "stdio",
      "command": "uvx",
      "args": [
        "deadends-dev"
      ]
    }
  }
}

Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.

ChatGPT connects only to servers on the internet:

  1. Open ChatGPT on the web → Settings → Connectors (Apps)
  2. Press Create or Add (some plans need Developer mode under Advanced first)
  3. Paste the address below, give it a name and save
  4. If it asks you to sign in, sign in with the maker
SettingsConnectors1+ Create2https://…3
https://deadends.dev/mcp

Menu names can differ slightly by plan and over time.

Your choice stays on this device in a cookie; no account needed.

These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.

What it can do

We have not read this server’s tool list yet; we check endpoints in rotation.

Basic checksi

We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 7, 2026

  • ✓ Pass

    Maker matches the repo

    The registry name was verified against the domain deadends.dev (the registry checks domain ownership)

  • … Not checked yet

    Still maintained

    We have not read this repo from GitHub yet

  • … Not checked yet

    Has a licence

    We have not read this repo from GitHub yet

  • … Not checked yet

    Endpoint responds

    Not checked yet; we check endpoints in rotation

  • … Not checked yet

    Sign-in with OAuth

    Not checked yet; we check endpoints in rotation

  • … Not checked yet

    No hidden instructions in tool descriptions

    Not checked yet; we read the tool list when we check the endpoint

Compared with others in Search & AI memoryi

  • More stars than 0% of the other 7254 servers in this category
  • Published to the registry more recently than 30% of the other 7254 servers in this category
  • Basic checks equal to or better than 100% of the other 7254 servers in this category

Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.

Common questions

Is deadends.dev safe?

It passed 1 of 1 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.

What keys or codes does it need?

The registry does not list a required key, though some servers ask you to sign in on first use.

Does it run on my computer or in the cloud?

Either way works: install it on your computer or connect to the cloud version.

Is it still maintained?

The GitHub repo last changed –, and the latest version (0.9.0) reached the registry 3 months ago.

Which apps can use it?

Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. It connects by URL, so apps that accept remote MCP servers work too, such as ChatGPT in developer mode.

What can I use instead?

In the same category: Context7, Codebase Memory, Exa

Alternatives

Servers in the same category from other makers, sorted by stars.

Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi

Context7

by upstash

Feeds AI the latest docs for libraries and frameworks before it answers, so code it writes does not use outdated, removed functions.

Computer or cloud★ 64,224MITUpdated today
Install

Codebase Memory

by DeusData

Codebase knowledge graph for AI agents — 162 languages, sub-ms queries, 99% fewer tokens.

Runs on your computer★ 48,148MITUpdated 20 days ago
Install

Exa

by exa-labs

Connect AI agents to Exa for web search, content fetching, and multi-step research.

Runs in the cloud★ 5,213MITUpdated last month
Install

README from the maker

Open the README

Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.

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.devWith deadends.dev
Agent tries sudo pip install → breaks system Python → wastes 3 retriesAgent sees "dead end: sudo pip - fails 70%" → skips it immediately
Agent tells user to tip 15% at a Tokyo restaurantAgent knows tipping is refused in Japan (culture/tipping-refused/jp)
Agent drafts a Thai social post referencing King Rama XAgent stops: Article 112 lèse-majesté risk (legal/lese-majeste-article-112/th)
Agent fixes error A, gets confused by error BAgent knows "A leads to B 78% of the time" → handles both
Agent tells unmarried couple to kiss publicly in DubaiAgent 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.

  1. 로컬 서버 모드인지, 원격(Smithery) 모드인지 하나만 사용
# 로컬 서버 확인 (정상 시 툴 목록이 출력됨)

python -m mcp.server --help

  1. Claude Desktop 설정 파일 점검 (cwd는 실제 경로여야 함)
cat ~/.claude/claude_desktop_config.json
  1. 로컬 서버 직접 실행 테스트
cd /path/to/deadends.dev

python -m mcp.server

  1. 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

  1. 마지막으로 Claude Desktop 완전 재시작
# macOS 예시

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

Single error lookup

result = lookup("ModuleNotFoundError: No module named 'torch'")

What NOT to try (saves tokens and time)

for d in result["dead_ends"]: print(f"AVOID: {d['action']} - fails {int(d['fail_rate']*100)}%")

What actually works

for w in result["workarounds"]: print(f"TRY: {w['action']} - works {int(w['success_rate']*100)}%")

Batch lookup (multiple errors at once)

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%)

MCP Tools (11)

ToolDescription
lookup_errorMatch an error message against 2000+ known patterns
get_error_detailFull canon by ID
list_error_domainsAll 54 domains with counts
search_errorsTF-IDF keyword search across all domains
list_errors_by_domainAll errors in a domain
list_errors_by_countryAll country-scoped dead ends for an ISO alpha-2 code
get_country_summaryCountry-level summary (entries, fix rate, domain mix)
batch_lookupLook up multiple errors at once (max 10)
get_domain_statsDomain quality metrics and confidence levels
get_error_chainTraverse the error transition graph
report_outcomeReport whether a workaround worked (feeds back into success rates)

API Endpoints

EndpointDescription
/api/v1/match.jsonLightweight regex matching (fits in context window)
/api/v1/index.jsonFull error index with metadata (entries include country field for country canons)
/api/v1/{id}.jsonIndividual ErrorCanon
/api/v1/countries.jsonCountry index with counts and update dates
/api/v1/country/{cc}.jsonPer-country aggregate (one call returns all entries for that country)
/api/v1/openapi.jsonOpenAPI 3.1 spec
/api/v1/stats.jsonDataset quality metrics by domain
/api/v1/errors.ndjsonNDJSON streaming
/llms.txtLLM-optimized listing (llmstxt.org)
/dashboard/Data quality dashboard

Covered Domains (54)

Code error domains (51)
DomainErrorsExamples
Python88ModuleNotFoundError, TypeError, KeyError, MemoryError, RecursionError
Node70ERR_MODULE_NOT_FOUND, EACCES, EADDRINUSE, heap OOM, ERR_REQUIRE_ESM
Docker65no space left, exec format error, bind address in use, healthcheck
Kubernetes61CrashLoopBackOff, ImagePullBackOff, OOMKilled, RBAC forbidden, HPA
Git60failed to push, merge conflicts, detached HEAD, stash apply, tags
CUDA57OOM, device-side assert, NCCL, cuDNN, tensor device mismatch
Go54nil pointer, unused import, interface conversion, slice out of range
Java54NullPointerException, ClassNotFound, OutOfMemoryError, connection pool
Database52deadlock, connection pool, slow query, replication lag
AWS51AccessDenied, S3 NoSuchBucket, Lambda timeout, CloudFormation rollback
.NET50NullReferenceException, LINQ translation, DI circular, EF concurrency
ROS 250node spin, launch error, QoS mismatch, tf2 transform
TypeScript49TS2307, TS2322, TS2345, TS2532, TS7053
Rust48E0382 borrow, E0308 mismatch, E0277 trait, E0106 lifetime
+ 37 more domains40+ eachCI/CD, PHP, Terraform, Networking, Next.js, React, pip, Android, ...
Country-scoped real-world domains (new, growing)
DomainCoversExample dead ends
visaPre-travel authorization, overstay, re-entry bansESTA 90-day rule (US), K-ETA (KR), ETIAS/EES (Schengen), Schengen 90/180 (DE)
bankingAccount opening, KYC, foreigner rulesARC required (KR), residence card 6-month (JP), SSN/ITIN (US)
emergencyCorrect emergency numbers, transit112 not 911 (DE), 999/101/111 (UK)
medicalInsurance, Rx import, coverageShaho/Kokuho (JP), NHIS 6-month (KR), EHIC ineligibility (DE), Adderall import ban (JP)
legalCriminal liability, contract norms§86a Nazi symbols (DE), Article 112 (TH), Article 301 (TR), alcohol ban (SA), key money (JP)
cultureEtiquette, taboos, social normsChopsticks in rice (JP), clock gifts (CN), Tiananmen silence, red ink names (KR), bonjour (FR)
food-safetyWater, pathogens, religious taboosTap water (MX), fugu license (JP), beef in India, pork in Indonesia
communicationLanguage register, terminologyHonorifics (KR), American War framing (VN), 'gringo' (MX), Cantonese vs Mandarin (HK)
safetyDriving, public-safety normsLeft-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 connecti

Only the beginning is shown; read the rest in the repo

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