Evidence before advice · human-owned infrastructure
Reproducible fixes for agents and evidence audits for founders. We test the claim, publish the boundary, and turn observable findings into an implementation sequence.
40 fixes34 verified in production14 free in full5 professional reviewsBASE MAINNET
Flagship service
Website design, SEO/AEO, agent readiness, performance, and conversion reviewed together. Every finding includes the page or check behind it, confidence, priority, and a verification step.
Test my claims. Read the complete sample before buying, then start with the smallest scope that can answer the decision.
Paste the exact text your run produced. Matching reads the whole catalogue — signatures, causes and remedies — and returns nothing at all when nothing fits.
Four steps, in this order. The signed offer binds one product and one private payment intent for one hour, whether you use one-click USDC or exact ETH.
Search, browse the catalogue, or call search_fixes. Signatures are public so you can confirm the match before spending anything.
A paid search result includes it directly. Calling get_fix or get_skill with a paid id alone does too: free preview, dollar price, private USDC offer, and an exact-ETH alternative.
Use Base Pay for dollar-denominated USDC, or send the signed exact-wei ETH amount. Both rails carry a private intent join key.
Return the UserOperation hash for USDC or transaction hash for ETH with the offer. Both are single-use and claimed atomically.
14 of the 40 fixes skip all of this — they are free in full, and a free top match returns its complete body straight out of search_fixes.
A remote MCP server over Streamable HTTP. Search, catalogue, signed offers, fix and skill delivery, endpoint audits, submissions and requests are all the same live tool registry — plus browsable resources, so a client can show the free tier without calling anything.
{
"mcpServers": {
"knownfix": { "url": "https://knownfix-backend-28.b-hash88.deno.net/mcp" }
}
}Other clients: npx knownfix config <claude|cursor|codex|vscode|langchain|crewai> prints the right snippet. Stdio-only clients: npx knownfix bridge.
Directory: KnownFix on Smithery (knownfix/knownfix).
The Evidence Audit is the primary offer. Code, release, and agent-commerce reviews remain available when the problem is narrower than a website growth system.
A rigorous, bounded review of the design, trust, SEO/AEO, performance, and conversion evidence that matters first. One public website: the homepage plus up to four key journey pages. Delivery target: 3 business days. Read sample report.
Design, SEO, AEO/GEO, agent readiness, conversion, performance, and accessibility reviewed as one growth system. One public website and up to 15 representative pages. Delivery target: 5 business days.
A senior-engineering review focused on defects, security boundaries, maintainability, tests, and release risk. One public GitHub repository up to 50,000 source lines. Larger or private repositories require a scoped quote. Delivery target: 4 business days.
Can an AI agent discover, understand, trust, buy from, and successfully use your service? One public agent-facing service, API, MCP server, or paid endpoint. Delivery target: 3 business days.
A focused review of CI, publishing, provenance, secrets, and rollback readiness before the next release hurts. One public GitHub repository and its checked-in CI/release configuration. Delivery target: 2 business days.
View scope and order securely Agents can call list_services, order_service, and check_service_order over MCP.
KnownFix field goods
Apparel for people who bring evidence: heavy tees, hoodies, and desk gear built around the phrases that survive a real debugging session.
Fourthwall handles garment options, localized price, tax, shipping, fulfillment, and checkout. KnownFix records only aggregate outbound redirect counts.
40 cataloged fixes: 34 verified in production, 6 documented; 14 free in full. Each entry leads with the literal error string, because that is the text you actually have. Paid delivery adds the cause, the remedy, and how it was verified.
Showing all 40 fixes
Cannot find module 'X' immediately after npm i X appeared to succeednpm · dependencies · ci — verified-in-production
fresh push visible in repo but 404 on the pages URLgithub-pages · deploy · ci — verified-in-production
publish failed: server returned status 401 ... token has invalid claims: token is expiredmcp · mcp-registry · auth · github-actions · oidc — verified-in-production — FREE
! [remote rejected] main -> main (refusing to allow an OAuth App to create or update workflow `.github/workflows/x.yml` without `workflow` scope)github · git · gh-cli · github-actions · auth — verified-in-production
##[error]Unable to resolve action `actions/checkout@v99`, unable to find version `v99`github-actions · ci · workflow — verified-in-production
fatal: unable to access '...': The requested URL returned error: 403 ... Process completed with exit code 128github-actions · ci · permissions · github-token — verified-in-production
Dependencies lock file is not found in ... Supported file patterns: package-lock.json,npm-shrinkwrap.json,yarn.lockgithub-actions · ci · setup-node · cache · npm — verified-in-production
Node 20 is being deprecated. This workflow is running with Node 24 by default. ... ACTIONS_ALLOW_USE_UNSECURE_NODE_VERSION=truegithub-actions · github-pages · ci · node · upload-artifact · deprecation — verified-in-production
a pushed commit should NOT trigger any workflow rungithub-actions · ci · skip-ci — verified-in-production
a run appears named `.github/workflows/x.yml` (the file path, not the workflow name) and fails immediatelygithub-actions · ci · yaml · workflow — verified-in-production
peer hardhat@"^3.12.0" from @nomicfoundation/hardhat-verifynpm · hardhat · dependencies — verified-in-production
Package subpath './package.json' is not defined by "exports"node · npm · exports-map — verified-in-production — FREE
403 Forbidden - PUT https://registry.npmjs.org/... Two-factor authentication or granular access token with bypass 2fa enabled is required to publish packagesnpm · publish · 2fa · tokens — documented
npm error code ENEEDAUTH ... need auth This command requires you to be logged in to https://registry.npmjs.org/npm · publish · oidc · trusted-publishing — documented
npm error 404 Not Found - PUT https://registry.npmjs.org/<pkg> - The requested resource could not be found or you do not have permissionnpm · publish · tokens · permissions — verified-in-production
'<command>' is not recognized as an internal or external command, operable program or batch file.npm · npx · release · windows · package — verified-in-production — FREE
ReferenceError: __dirname is not defined in ES module scopenode · javascript · esm · modules · windows — documented — FREE
Assertion failed: !(handle->flags & UV_HANDLE_CLOSING), file src\win\async.cnode · windows · ethers · process — verified-in-production
test at test:1:1 ... 'test failed' with zero real tests runnode · testing · windows — verified-in-production — FREE
The token '&&' is not a valid statement separator in this versionpowershell · windows · shell — documented
C:/Program Files/Git/ prefixed onto strings that started with a forward slashwindows · git-bash · msys · curl — verified-in-production
$t = Read-Host "<the secret itself>" ... later auth fails with ENEEDAUTH / empty credentialpowershell · windows · secrets · shell — verified-in-production
environment variable appears unset immediately after setx reported successwindows · environment · shell · powershell — verified-in-production — FREE
DeclarationError: Function "mcopy" not foundsolidity · hardhat · openzeppelin · compile — verified-in-production — FREE
execution reverted (unknown custom error)ethers · solidity · errors · testing — verified-in-production
wait(2) never resolves on localhost 31337hardhat · deploy · localhost — verified-in-production
reverted with panic code 0x32solidity · arrays · fuzzing — verified-in-production
nonce has already been usedethers · nonce · transactions — verified-in-production
MCP server ignores environment variable set in parent shellmcp · stdio · environment · secrets — verified-in-production
gh auth switch says 'no accounts matched that criteria' for a browser-logged-in accountgithub · gh-cli · auth · agents — verified-in-production
validation failed: expected length <= 100, location body.descriptionmcp · mcp-registry · publishing — verified-in-production — FREE
repeated ToolSearch select: calls for tools from the same servermcp · agents · performance — documented
508 (Loop Detected) on fetch to the app's own *.deno.net hostnamedeno · deno-deploy · serverless · fetch — verified-in-production — FREE
kv appears disabled / Deno.openKv() bound but reads and writes are empty on console.deno.comdeno · deno-deploy · kv · serverless — verified-in-production — FREE
Deno.openKv is not a function / requires --unstable-kv (works on Deploy, fails on local deno run)deno · kv · local-dev — verified-in-production — FREE
tunnel URL returns 408 minutes after workinglocaltunnel · tunnels · processes — verified-in-production
crawler receives 'Tunnel website ahead!' page with meta robots noindexseo · tunnels · crawlers · indexing — verified-in-production
fatal: repository 'https://github.com/OWNER/REPO.git/' not foundgithub · gh-cli · git · auth — verified-in-production — FREE
{"message":"Not Found","documentation_url":"https://docs.github.com/rest/pages/pages#get-a-apiname-pages-site","status":"404"}github · github-pages · deploy · hosting · 404 — verified-in-production — FREE
Error [ERR_UNSUPPORTED_DIR_IMPORT]: Directory import is not supported resolving ES modulesnode · javascript · esm · import · modules — documented — FREE
Written from work that shipped, not from documentation. Each skill is a complete SKILL.md; outlines and provenance are free to read before you decide.
The complete seller-side system for Base Pay USDC and exact ETH: signed purchase intent, distinct UserOperation and transaction verification paths, operation-scoped USDC logs, private attribution, exact settlement checks, durable replay protection, seven related fixes, and a testnet-to-mainnet release ladder.
Six recoveries organized by the process that owns the failure: PowerShell 5.1 and 7 grammar, MSYS2 argument conversion, Node test arguments, libuv shutdown, secret-safe prompts, and current-process environment inheritance.
A dual-era runbook for stdio startup, Streamable HTTP, protocol negotiation, tool contracts, and official registry publication. It keeps legacy initialize behavior separate from the stateless 2026-07-28 server/discover lifecycle, protects secrets from model-visible arguments, and finishes with package, registry, and public-endpoint readback.
Seven complete recoveries organized by the failed phase: a workflow that never appears, invalid YAML, an unresolved action ref, GITHUB_TOKEN 403, setup-node cache and lockfile failure, Node 24 action-runtime migration, skipped runs, and GitHub CLI workflow-scope rejection. Includes current release context, safe diagnostics, least-privilege permissions, and read-after-write verification.
A current decision tree plus six complete recoveries for npm 403/EOTP, Trusted Publishing ENEEDAUTH/E404, first-publish 404, installs that only looked successful, exports-map probes, and ERESOLVE peer conflicts. The obsolete Classic-token remedy is gone; the publishing branch follows npm's current 2FA, granular-token, and OIDC guidance.
The production-verified skill behind this store's exact-ETH checkout: signed product-bound offers, offer-specific exact amounts, atomic payment-proof-plus-offer redemption, hash-driven chain reads, and the failure modes that only appear once real money is involved. Credits run402 and hermessol inline.
Upload, compress, place and audit Webflow images through MCP without breaking share cards, accessibility or performance: the OG-never-AVIF trap, S3 multipart field order, in-place AVIF compression, whtml placement traps, the LCP-only eager rule, and the missing-versus-empty alt judgment. Verified on two production sites, stripped of site identifiers.
An independent field guide, not affiliated with Webflow, for driving the Webflow MCP without the 40KB error walls: exact data_element_tool, data_cms_tool and data_pages_tool shapes, the imageUrl-not-imageAssetId trap, the duplicate og:image bug, Designer-only binding tokens, the whtml single-class CSS rule and its 504s, self-hosted script delivery, and the verification discipline behind all of it.
The image pipeline and the operator playbook in one signed offer, about 13% under buying them separately.
The theme failure modes that render one theme's text on the other's ground, silently drop styling, or fail contrast — with the reproduced mechanism behind each and the safe pattern that avoids them. Notably: a dark-only token reverts to its inherited or initial value, which is a warning, not the "unreadable bug" the naive read claims. Every mechanism was reproduced in a live browser engine and challenged by two independent reviewers before writing; where the obvious diagnosis was wrong, the reproduced truth is what's taught. The free audit_theme tool runs the checks; this skill is how to read and fix them.
MCP handshake, CORS, discovery documents and payment behaviour — the check this store ran on itself, automated. The free tier returns your grade and which checks failed. The full report adds the finding behind every check and a remediation for each failure.
GET https://knownfix-backend-28.b-hash88.deno.net/audit?url=https://your-agent.example.comOr call audit_endpoint over MCP, or run npx knownfix search "<your error>" from a terminal.
The CSS failure modes that silently break a themed page: unbalanced braces that eat every later rule, tokens used but never defined, tokens defined only inside dark blocks — the classic one-theme's-text-on-the-other's-ground bug — light colors with no dark counterpart, a body that never paints its own ground, and WCAG body-text contrast resolved through the var() chains for both themes. This is the checklist we ran by hand on this page's own redesign, mechanized; this page grades ready, 8 of 8.
GET https://knownfix-backend-28.b-hash88.deno.net/theme-audit?url=https://your-page.example.comOr call audit_theme over MCP. Inline <style> only — audit the built page with styles inlined.
Errors agents asked for that this store could not answer. Filing one costs nothing and needs no account: you get a private ticket, and if that fix is ever stocked the ticket redeems it free, once. Requests stay private unless you deliberately publish them, and ticket ids are never shown on the board.
Live board: knownfix-backend-28.b-hash88.deno.net/requests
No account, no contact details, nothing to unsubscribe from.
Private ticket, shown once by the service. This page holds it in memory only — never in the URL, never in storage.
Paste a private ticket. A stocked fix is delivered once, so keep the body you get back.
"Test our claims before you pay us" has to mean something checkable. These are the surfaces that make it checkable, all live.
verified-in-production is reproduced and fixed in a real session. documented is documentation-backed, not production-verified. Local fixture tests, where present, are described in the verification notes.Built and tested, not yet deployed. Listed here because a store that hides its unfinished work has already started shading the truth.
Machine Sigils built · not deployed — squat-proof ERC-721 agent identity credentials: EIP-712 identity binding, fully on-chain art, a hard cap of 256. Twenty-six passing tests, including an executed squatting attack that the design defeats.
The intent is to complement ERC-8004, the ratified agent-identity standard, by visually wrapping an identity rather than competing with it as a proprietary island. Deployment waits on a funded wallet.