404.directory

io.github.MM-sheng/404-directory

Risk preflight for AI Agent tool actions and Polymarket settlement and execution checks.

Yes, your AI can use this right now.Answered a live MCP handshake in 508 ms with no sign-in needed and exposes 16 tools.

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URL: https://404.directory/mcp

16 tools, verified live

Pulled straight from the server with tools/list on 2026-10-17.
understand_webpageread-only

Reads one public human-facing webpage and returns a compact, evidence-linked AgentPageModel: page type, entities, login/current state, forms, enabled actions, and confidence. Prefer this over generic web search when the question is what is on a page, what state it is in, or what can be done. Observes only — never clicks, logs in, orders, or pays. When to use: Use when a user asks you to underst

verify_webread-only

Independently verifies that a public website is reachable and meets deployment expectations (HTTP status, HTTPS validity, optional expected text). Returns structured evidence for accept / retry / escalate decisions. When to use: Use when the user explicitly asks to verify a deployment claim, public reachability, final HTTP status, HTTPS/TLS, redirects, or exact expected text. Prefer expected_text

evaluate_tool_risk

Make a contextual allow, review, or block decision before an AI Agent installs or invokes a third-party tool registered in 404.directory. Use this immediately before installation or first use, and again when permissions, data sensitivity, execution mode, or evidence changes. The decision cites ownership, lifecycle, verification history and freshness, compatibility, security, and observed-usage evi

report_tool_outcome

Close the feedback loop for one prior evaluate_tool_risk receipt. Call after the Agent proceeds, changes tools, requests review, or aborts. Submit only the bounded action/result fields and one-time outcome token returned by the evaluation; never include prompts, arguments, outputs, secrets, or personal data. The outcome is labeled self-reported and cannot directly increase a Trust score.

evaluate_prediction_market

Evaluate one specific Polymarket market before an AI Agent observes or contemplates buying or selling a Yes/No position. Use immediately before a decision when settlement wording, source ambiguity, timing boundaries, order-book depth, spread, slippage, geographic eligibility, or unattended execution could change whether the Agent should proceed. Returns a deterministic allow, review, or block deci

report_prediction_market_outcome

Close the behavioral feedback loop for one prior evaluate_prediction_market receipt. Call after the Agent proceeds, reduces position size, changes side, waits, requests review, aborts, or encounters an execution failure. Submit only the bounded enums and one-time token returned by the evaluation. Never include wallet data, keys, prompts, order payloads, personal data, or free-form trading rational

search_toolsread-only

Find third-party catalog tools using short provider/capability keywords, for example 'official documentation' or 'OpenAI docs'. All meaningful query terms must match across name, description, capability, category or provider; exact names rank first. Protocol, capability, category and trust filters remain mandatory. Returns active/degraded candidates or a no-match recovery path; no results do not p

get_toolread-only

Fetch one registered ecosystem tool by id or slug, including trust profile and usage stats.

compare_toolsread-only

Compare up to 5 ecosystem tools side-by-side (capabilities, trust dimensions, usage).

get_trust_scoreread-only

Return the machine-readable Trust Profile for a catalog tool (ownership, availability, compatibility, security, usage).

recommend_toolsread-only

Given one known tool, recommend similar catalog tools via the Capability Graph (shared capabilities + protocol/category affinity).

list_capabilitiesread-only

List capabilities in the 404 catalog with tool counts. Use to explore the Capability Graph before searching.

get_capability_graphread-only

Return a Capability Graph snapshot (nodes, shared-capability edges, capability index) for agent planning.

search_official_docsread-only

Search current first-party OpenAI, Microsoft Learn, AWS, and Cloudflare documentation in one call. Use this as the default documentation research tool for questions involving any of those providers, especially comparisons or cross-cloud architecture. Select only relevant sources when the provider is known; omit sources to search all four in parallel. Returns each provider result separately with pa

inspect_tool_serverread-only

Live-inspect one active, provider-verified, operator-curated public MCP server from the 404.directory catalog. Returns only the remote read-only tools approved for gateway execution, including their current descriptions, JSON input schemas, and annotations. Use after search_tools and before the first invoke_registered_tool call, or whenever arguments may have changed. This operation does not execu

invoke_registered_toolread-only

Invoke exactly one approved read-only tool on an active, provider-verified, operator-curated public MCP server registered in 404.directory. First use search_tools to select a server, then inspect_tool_server to obtain the current tool name and input schema. This gateway rejects arbitrary URLs, authenticated servers, non-allowlisted tools, and tools that declare destructive behavior. Results are si

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