mcpbeat Sign in

Overwing MCP Server

not responding

Overwing is listed as active in the registry but did not answer our last check. 115 installs a week from npm. It exposes 41 tools. Last commit 14 Oct 2026.

Guardrails for LLM output: pass / fail / review verdicts and one recommended action. Hosted or npm.

Installs per day peak 453 · avg 85 · +3% w/w
a month agotoday
Uptime history 42 days of history · worst day 0%
42 days agonow
1.1%
Uptime 24h
1 of 92 checks
41
Tools
read from the server
321 ms
Response time
average over 24h
115
Installs / week
npm and PyPI

What changed 17

Every tool that appeared, vanished or quietly changed what it asks for. Recorded since 8 October 2026. No other catalogue keeps this.

18 Oct 7 tools appeared feedback, preflight_check, preflight_overview and 4 more
8 Oct 7 tools appeared atlas_list_registrations, atlas_register_agent, atlas_verify_registration and 4 more
8 Oct 3 tool descriptions were rewritten beacon_report, beacon_sample, beacon_start

Overwing does not always answer

Over the last week it answered 0.3% of our checks. We check every 15 minutes, so you hear about the next outage within the hour — not from your users.

Three servers free · no card

Connect this server

Endpoint below is the one we actually reach during checks — not the one copied from a README. Last verified 0 min ago.

run in your terminal
claude mcp add mcp --transport http https://overwing.ai/mcp
Settings → Connectors → Add custom connector, then paste this address
https://overwing.ai/mcp
~/.codex/config.toml
[mcp_servers.mcp]
url = "https://overwing.ai/mcp"
.cursor/mcp.json
{
  "mcpServers": {
    "mcp": {
      "url": "https://overwing.ai/mcp"
    }
  }
}
.vscode/mcp.json
{
  "servers": {
    "mcp": {
      "type": "http",
      "url": "https://overwing.ai/mcp"
    }
  }
}

Available tools 41

Read directly from the server with tools/list, grouped by what they act on. If a tool disappears, we record the date.

tower
tower_capabilities
List the operations this agent is allowed to call, each with the JSON Schema its input must match and its compensating operation. Call this first; build inputs from the schema rather than guessing. Needs an agent key.
tower_compensate
Run the compensating operation for an executed action, for example cancel the order that create_order made. Runs once; repeating it returns the first outcome. Needs an agent key.
tower_create_agent
Create a scoped agent identity and its key. Needs an organization key. Scope it to the operations the agent needs (for example create_order) rather than * where you can. The key (ow_agent_...) is returned once, in this result, and this server does not keep it: store it, and send it as the Authorization bearer on a connection used for the agent tools (tower_capabilities, tower_decide, tower_submit_action, tower_get_action, tower_compensate, tower_get_receipt, tower_verify_receipts). Revoke with tower_revoke_agent.
tower_decide
Ask Tower how it would rule on an operation without doing anything: auto (would execute), review (a person must approve), or reject. Returns the score, the reason, and each policy question's answer. No side effects. Needs an agent key.
tower_get_action
Status and result of an action: pending, approved, executed, failed, compensated, or rejected. Use it to poll an action that is waiting on human review. Needs an agent key.
tower_get_receipt
Fetch one signed receipt by id or by sequence number: the payload, its hash, the previous link's hash, and the Ed25519 signature. Needs an agent key.
tower_list_agents
List this organization's Tower agents with scopes, status and last use. Keys are never returned. Needs an organization key.
tower_load_template
Set up Overwing Tower for this organization by loading the starter workflow: email purchase order to order entry, with create_order, update_order and cancel_order against a mock IBM i system, and a starter policy. Idempotent. Needs an organization key. Returns a sample input you can submit. Next: tower_create_agent.
tower_revoke_agent
Revoke an agent. Its key stops working at once and cannot be restored. Needs an organization key.
tower_submit_action
Ask Tower to perform an operation on the legacy system. Tower decides: executed (done), pending (a person must approve; poll tower_get_action, do not resubmit), or rejected (do not retry unchanged). Always send an idempotency_key that is stable for this business request, such as the source message id: repeating a key returns the original outcome instead of acting twice. Set dry_run to see the decision without executing. Needs an agent key.
tower_verify_receipts
Recompute every hash and check every signature over a range of this organization's receipts. Reports the first break, if any. Defaults to the whole chain (up to 5,000 links per call). Needs an agent key.
atlas
atlas_agents
Browse or search Overwing Atlas, the registry of AI crawlers, fetchers and browser agents: name, operator, user-agent tokens, Web Bot Auth key directory, robots.txt behaviour, and (with Atlas Pro or Team) purpose class, verification, evasion flags and traffic shares. Filter by free text, purpose (training, search, browser, coding), operator, or verification. Needs an organization key.
atlas_list_registrations
The agents this organization has registered in Overwing Atlas, newest first, each with its status (pending_verification, pending_review, published, rejected) and, while unverified, the value to publish at the domain. Needs an organization key.
atlas_lookup
Say what a User-Agent string claims to be and whether the claim can be trusted, from the Overwing Atlas registry of AI crawlers, fetchers and browser agents. Returns the claimed agent, operator, purpose class, verification method (Web Bot Auth signature, user-agent string only, or unattributable) and a trust note. Works with no API key: 10 lookups a day. With a key, metered per day by Atlas tier: free 100, Pro 10,000, Team 100,000. Use it when deciding whether to serve, block, or pay-gate a request, or to understand who is hitting a site.
atlas_register_agent
Add an agent or crawler you operate to the Overwing Atlas registry, free, so a site that looks up its User-Agent learns who runs it. Give the agent's name, the operator (the company or person running it), the operator's domain, and the token the User-Agent carries (the product name, such as AcmeBot). The answer carries one value to publish at that domain, as a DNS TXT record or as a file under /.well-known, to prove control of it; then call atlas_verify_registration. A token may not match, contain, or sit inside one already in the registry. This proves control of the domain, not that any given request is yours: the entry is listed as user-agent only unless key_directory_url is a Web Bot Auth key directory on that domain. Only register agents you or your operator actually run. Needs an organization key.
atlas_summary
Public numbers from Overwing Atlas: registry counts by purpose and verification, published browser-agent traffic shares, sector field-scan headlines (e.g. how many OSINT sites carry AI-crawler rules or any agent-payable surface), and the summary of the Agent Consumers report on what agents actually spend. No key needed.
atlas_verify_registration
Look for the proof at the operator's domain: the DNS TXT record or the file that atlas_register_agent asked for. Found: the entry is published in the registry, or held for a person when the operator name already belongs to someone. Not found: an error saying what was looked for; DNS changes can take a few minutes, and calling again is safe. Needs an organization key.
atlas_withdraw_registration
Withdraw a registration. A published entry leaves the registry, so lookups stop naming the agent; an unfinished request is abandoned. This cannot be undone: register again to put it back. Needs an organization key.
preflight
preflight_check
Call this before signing any Solana transaction. Overwing Preflight simulates the unsigned transaction against the chain as it is now, works out what it would take from the wallet you name (SOL, tokens, and control of its token accounts) and answers allow or refuse against your policy, with every reason. Sign only if decision is "allow". Treat a refusal, an error, or anything else as do not sign. A verdict describes one moment and covers a transaction that lands within about two minutes, so sign and send at once or check again. This tool takes the serialized transaction and a policy; it never needs a private key and must never be given one. One check counts as one evaluation. Needs an organization key.
preflight_overview
The reference for Overwing Preflight: every policy field, every reason code a refusal can carry, what a verdict does and does not promise, the price, and the terms of the guarantee. Read it once before the first preflight_check. No key needed.
preflight_payment
Call this with the 402 you were given, before signing an x402 payment. It reads the terms (network, asset, amount, payee, timeout, resource) and answers allow, review or refuse with reasons: the terms against your policy, the payee against x402-list's directory (verified delivery, recorded settlements, buyers, shared payout addresses) and the server's own /.well-known/x402 manifest, and the price against what is recorded for that endpoint. Not a simulation and not a guarantee. Sign only on allow; on review, ask the person you work for. No key needed for a few checks a day.
preflight_record
Everything Preflight has said and how it held up: counts of verdicts and misses, every miss with what the chain showed, the latest verdicts, and what the guarantee's reserve holds. Read it before deciding whether to rely on Preflight. No key needed.
preflight_report
After a transaction that Preflight allowed has landed, report its signature. Preflight reads the landed transaction from the chain and says whether the allow held: not_a_miss, or miss when it took more from the wallet than the policy permitted. The outcome is published. A covered miss is paid to the wallet in the verdict, never to whoever reported it. No key needed.
preflight_verdict
The public record of one Preflight verdict: its decision, reason codes, the programs the transaction would run, the transaction's digest, our signature, and every landed transaction reported against it. Never the wallet, the amounts or the transaction. No key needed.
beacon
beacon_report
The report for a check started with beacon_start. The first call runs the check. With an Overwing key on the connection: score (0 to 100), verdict (yes, partly, no), the find / read / use answers, every check with what was found and a fix when it did not pass, and top_fixes ranked by value. With no key, the summary of the same report: score, verdict, the three answers and the first fix (access=summary). Answers 202 while the check is running (ask again in a few seconds). No key needed for the summary.
beacon_sample
A real Overwing Beacon report, free: the check of overwing.ai itself, refreshed daily. Read it to see exactly what a full report holds before starting a check. No key needed.
beacon_start
Overwing Beacon answers one question about a site: is this product reachable by agents? It checks robots.txt rules for AI agents, llms.txt, the sitemap, the MCP server card, hosted MCP endpoint and MCP Registry listing, the A2A agent card, OpenAPI discovery, and how the home page reads to a model, then returns three answers (find, read, use), a score and the fixes worth making. This tool starts a check and returns its id; it is free. Then call beacon_report with the id, which runs the check (about twenty seconds). With an Overwing key on the connection beacon_report returns the full report and the check is saved to that dashboard; with no key it returns the summary: the score, the three answers and the first fix. A key is free (POST /api/v1/signup). An agent with a wallet and no account can instead pay $1 in USDC over x402 and get the full report in one call: GET /api/x402/beacon?url=<site>. Call beacon_sample to see a real report in full. No key needed.
rule
create_rule_set
Create a custom rule set with 1 to 25 rules. Each rule is a choice (pick one option), score (position on an ordered scale), or noul (yes/no) question with a fail condition, optional review threshold, weight, and action (block, redact, or review) that callers should take when it fails. Rule instructions may reference `context.*` fields that callers pass with each evaluation. Needs an organization key.
get_rule_set
Fetch a rule set with its full rule definitions. Use 'content-safety' as a worked example when writing your own. Needs an organization key.
list_rule_sets
List the prebuilt and custom rule sets available to this organization. Needs an organization key.
evaluate
evaluate
Works with no API key: 10 evaluations a day, inputs up to 2,000 characters, and the text is not stored. With a key: 250 a day and up, inputs up to 100,000 characters, and your own rule sets. Score any text (typically an LLM's output) against an Overwing rule set. The text can be in any language; tested in Spanish, Portuguese, French, German, Japanese, Chinese, Korean, Arabic and Hindi. Results come back in English. Returns an aggregate verdict of pass, fail, or review, a recommended_action (block, redact, review, or allow), and per-rule answers with probability, confidence, and the rule's action. Act on recommended_action: block means do not send, redact means remove the flagged content and resend, review means ask a human or a slower model, allow means proceed. Prebuilt sets: 'content-safety' (toxicity, PII, self-harm, sexual content, severity) and 'outbound-message', which also takes a context object (recipient, channel, owns_contact_info) so PII that the recipient already owns is not flagged.
evaluate_batch
Score up to 50 texts against one rule set in a single call. Each item counts as one evaluation. Returns a summary plus per-item verdicts; items can fail independently. Needs an organization key.
account
create_account
Create an Overwing account for yourself, with no email: an organization and an API key, returned once. Nothing is sent to anyone. Use it when you have no key and nobody has given you one; do not create a second account if you already have a key (whoami says which account a key belongs to). The key is the account, so store it at once: with no email there is no reset link. It starts at 50 evaluations a day with Beacon summaries; proving a domain (prove_domain, verify_domain) raises that to the normal free limits and full Beacon reports, and makes a lost key recoverable. This server does not keep the key: send it as Authorization: Bearer on the MCP connection for the tools that need one. Tell the person you work for that you made the account and where the key is kept. No key needed.
evaluation
get_evaluation
Fetch a stored evaluation by id, including the original input and per-rule results. Needs an organization key.
evaluations
list_evaluations
List recent evaluations, newest first, with optional verdict and rule set filters. Use next_cursor to page. Needs an organization key.
feedback
feedback
Send one message to the people who run Overwing: a verdict you think was wrong, an error you could not act on, a payment you could not make, a tool that did not do what its description says. Read by a person, not answered automatically; give a contact if you want an answer. No key needed.
plans
list_plans
Public plan catalog: prices, daily limits, and per-minute burst limits. No API key needed.
prove
prove_domain
Begin proving that your account controls a domain. For an account with no email the domain stands in for one: it raises the limits to the normal free tier, opens full Beacon reports, and lets a lost key be replaced. Returns one value to publish at the domain, as a DNS TXT record or as a file under /.well-known; then call verify_domain. One domain belongs to one account. Calling again for the same domain returns the same value. Needs an organization key.
usage
get_usage
Daily usage, remaining quota for today, and plan limits. Needs an organization key.
verify
verify_domain
Look for the value prove_domain asked for, at the domain. Found: the domain is the account's. Not found: an error saying what was looked for; DNS changes can take a few minutes, and calling again is safe. Needs an organization key.
whoami
whoami
Identify the organization and plan behind the API key on this request, the key's scope, the organization's data settings (store_inputs, retention_days), and whether billing is set up. Needs an organization key.

Endpoints

URLTransportStateLatencyChecked
https://overwing.ai/mcp streamable-http answering 110 ms 0 min ago

Alternatives to Overwing

same job, measured the same way
GroundLens
by groundlens-dev

Guardrails for LLM answers: exact checks against sources, PASS/REVIEW/FAIL, signed records.

442 installs/wk local only
Evalsnap
by cloudcorprecords

Snapshot diff for agent and tool outputs: changed cases, score regressions, pass/fail verdict.

328 installs/wk local only
Governance Platform
by geodesiclabs

Pre-execution governance for AI agents. Deterministic PASS/FAIL/REVIEW verdicts, replayable proof.

37 tools answering
Most Recommended Books
by mostrecommendedbooks

Read-only MCP server for verified book recommendations and reading lists.

6 tools answering
Tracelane MCP
by tracelane

Read-only, tenant-scoped access to Tracelane agent traces and guardrail verdicts

42 installs/wk local only
Aidimag
by aidimag

Persistent, verified memory for AI coding agents: recall, capture, guardrails, review queue.

local only
Human For AI
by humanforai

Hire a real human for real-world verification, product testing, AI output review, and errands.

47 installs/wk 6 tools answering
Freshdeps MCP
by solvohq

Live npm/PyPI dependency-health verdicts so AI agents stop recommending stale or CVE'd packages

local only

Overwing — questions

Answers built from our own checks of this server.

What can Overwing do?
It exposes 41 tools, read directly from the server on our last check. Among them: atlas_agents, atlas_list_registrations, atlas_lookup, atlas_register_agent, atlas_summary, atlas_verify_registration and 35 more. The full list with descriptions is on this page — we take it from the server itself via tools/list, not from a README. How MCP servers expose tools in the first place →
What is Overwing mostly used for?
Its tools cluster around tower, atlas and preflight. That is what this server is built to work with — the grouping comes from the actual tool names, not from a category we assigned.
Is Overwing working right now?
We send a real MCP handshake every 15 minutes. Over the last 24 hours 1 of 92 checks got a reply (1.1%), average response time 321 ms. The bar chart above shows every period we have measured.
The registry lists Overwing as active — why does it not respond?
The official MCP registry stores what the author submitted; it does not verify that the server still runs. We check the endpoint ourselves, and this one does not answer. Catalogues that copy the registry without checking will show it as working.
How do I connect Overwing?
Copy the ready config from this page. We generate it for Claude Code, Claude Desktop, Codex, Cursor and VS Code, each in the form that client actually reads. It is a remote server, so there is nothing to install — the client connects to the address.
Does Overwing need an API key?
No. Overwing completed a full MCP handshake with us as an anonymous client and listed its tools without asking for anything. All 41 of them are readable on this page. This is what we observed, not what the docs claim.
How fast is Overwing?
It answers our handshake in 321 ms on average, which is faster than 43% of all working MCP servers we measure. The comparison comes from our own checks across the whole registry, every 15 minutes.
How many people use Overwing?
The npm package overwing-mcp was installed 115 times in the last week. Week over week that is +3%. We show installs rather than GitHub stars on purpose: a star is a bookmark, an install is someone actually running it.
Is Overwing open source?
The code is open source: it is published under the MIT licence, written in TypeScript, 0 stars on GitHub and 3 open issues. The licence covers the code in the repository, not the hosted service at overwing.ai, which runs on its operator's own terms.