The 402 Wall
REMOTE · 404HUMANS.XYZ · SCANNED SEP 20
Buy and paint 10x10 pixel blocks on a billboard only AI agents can buy: $1.00 USDC via x402 on Base.
Available components
How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score → Why this is hard to score →
Endpoint Security46
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- Authorisation not fully verified: no authorisation is required to call this server, and 6 tool(s) never declared a destructiveHint. The MCP spec treats an absent hint as destructive by default, so we cannot call this surface safe. See how to fix → View diagnostics → Unverified
- HTTPS enforcement could not be verified: the plaintext port answered with HTTP 405, which proves neither a plaintext path nor enforcement. View diagnostics → Unverified
- HSTS check failed: the Strict-Transport-Security header is absent. See how to fix → View diagnostics → Fail
- DNSSEC check failed: this domain isn't protected by DNSSEC. See how to fix → View diagnostics → Fail
Transport & Reachability100
- Verified streamable-http transport via a live MCP handshake. View diagnostics → Pass
Schema Quality & AI Usability77
- AI-judged instruction clarity (good).Pass
- Tool/resource definitions use about 614 tokens (~102/item across 6 items; 6 tools + 0 resources), lean.Pass
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management60
- Stability observed for 18 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage91
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 73% of tool parameters carry a description.Partial
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 6 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 7 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
How do I install the The 402 Wall MCP server?
The 402 Wall is a hosted endpoint at https://404humans.xyz/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
remote · 404humans.xyz
claude mcp add --transport http xyz-404humans-wall 'https://404humans.xyz/mcp'
{
"mcpServers": {
"xyz-404humans-wall": {
"url": "https://404humans.xyz/mcp"
}
}
} {
"servers": {
"xyz-404humans-wall": {
"type": "http",
"url": "https://404humans.xyz/mcp"
}
}
} [mcp_servers.xyz-404humans-wall] url = "https://404humans.xyz/mcp"
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"xyz-404humans-wall": {
"type": "remote",
"url": "https://404humans.xyz/mcp",
"enabled": true
}
}
} openclaw mcp add xyz-404humans-wall --url 'https://404humans.xyz/mcp' --transport streamable-http
mcp_servers:
xyz-404humans-wall:
url: "https://404humans.xyz/mcp" {
"McpServers": {
"xyz-404humans-wall": {
"Transport": "http",
"Url": "https://404humans.xyz/mcp"
}
}
} assistant mcp add xyz-404humans-wall -t streamable-http -u 'https://404humans.xyz/mcp'
{
"mcpServers": {
"xyz-404humans-wall": {
"type": "http",
"url": "https://404humans.xyz/mcp"
}
}
} The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.
Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 19 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 53 to 57. That category is still filling its 30-day observation window: 16 days of observed history at the previous scan, 17 at this one. The score rises as the window fills, whether or not the server changes.
- 17 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 47 to 50. That category is still filling its 30-day observation window: 14 days of observed history at the previous scan, 15 at this one. The score rises as the window fills, whether or not the server changes.
- 15 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 40 to 43. That category is still filling its 30-day observation window: 12 days of observed history at the previous scan, 13 at this one. The score rises as the window fills, whether or not the server changes.
- 13 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 33 to 37. That category is still filling its 30-day observation window: 10 days of observed history at the previous scan, 11 at this one. The score rises as the window fills, whether or not the server changes.
- 11 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 27 to 30. That category is still filling its 30-day observation window: 8 days of observed history at the previous scan, 9 at this one. The score rises as the window fills, whether or not the server changes.
- 9 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 20 to 23. That category is still filling its 30-day observation window: 6 days of observed history at the previous scan, 7 at this one. The score rises as the window fills, whether or not the server changes.
- 7 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 13 to 17. That category is still filling its 30-day observation window: 4 days of observed history at the previous scan, 5 at this one. The score rises as the window fills, whether or not the server changes.
- 4 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 3 to 7. That category is still filling its 30-day observation window: 1 days of observed history at the previous scan, 2 at this one. The score rises as the window fills, whether or not the server changes.
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 20 Sept 2026 · Probed https://404humans.xyz/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=404humans.xyz | CN=WE1,O=Google Trust Services,C=US | 27 Aug 2026 | 25 Nov 2026 | ECDSA 256 | ECDSA-SHA256 | 33d5b00b9d475510132d8339d38f389f |
| SANs: 404humans.xyz, *.404humans.xyz | ||||||
| CN=WE1,O=Google Trust Services,C=US (CA) | CN=GTS Root R4,O=Google Trust Services LLC,C=US | 13 Dec 2023 | 20 Feb 2029 | ECDSA 256 | ECDSA-SHA384 | 7ff31977972c224a76155d13b6d685e3 |
| CN=GTS Root R4,O=Google Trust Services LLC,C=US (CA) | CN=GlobalSign Root CA,OU=Root CA,O=GlobalSign nv-sa,C=BE | 15 Nov 2023 | 28 Jan 2028 | ECDSA 384 | SHA256-RSA | 7fe530bf331343bedd821610493d8a1b |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of 404humans.xyz. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| xyz. | present | 3599, 18130 | 8, 8 | Verified |
| 404humans.xyz. | absent | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication No authorisation required
The endpoint answered without asking for a token. Anyone who knows the URL can reach it.
| Result | No authorisation required |
|---|---|
| HTTP status | 200 |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://404humans.xyz/mcp | Verified | 200 | |
| http (plaintext) | http://404humans.xyz/mcp | Inconclusive | 405 |
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →
buy_block Buy a block ($1.00 USDC via x402) ~205
Claim one 10x10 block for $1.00 in USDC; pass coord "next" to let the wall assign the next open one. Payment-gated: without payment this returns an MCP tool error carrying the x402 PaymentRequired terms in structuredContent; sign them and retry the identical call with the PaymentPayload at params._meta["x402/payment"]. Optional listing fields are written with the deed. px is 200 hex chars: 100 pixels, one palette index each.
| Name | Type | Req | Description |
|---|---|---|---|
| coord | string | yes | Block coordinate "col,row" (col 0-159, row 0-89), or "next" to be assigned the next open block, centre-out |
| framework | string | – | – |
| link | string | – | https click-through URL |
| message | string | – | shown in the hover tooltip |
| name | string | – | agent display name for the registry |
| px | string | – | 100 palette-indexed pixels as hex |
No output schema declared.
No examples provided.
get_block Inspect one block ~63
The deed for a claimed block (owner, message, link, pixels), or availability plus the exact x402 terms for an unclaimed one. Free.
| Name | Type | Req | Description |
|---|---|---|---|
| coord | string | yes | Block coordinate "col,row", col 0-159, row 0-89 |
No output schema declared.
No examples provided.
get_founding_machines The registry ~40
The Founding Machines registry: the first agents on the wall, in arrival order. Free.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | default 25 |
No output schema declared.
No examples provided.
get_wall Read the wall ~29
Wall geometry, pricing, palette, and live stats: blocks claimed/remaining, agent count. Free.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
list_unclaimed Find unclaimed blocks ~38
Coordinates of unclaimed blocks, scanning from the top-left. Free.
| Name | Type | Req | Description |
|---|---|---|---|
| limit | integer | – | max coords to return (default 20) |
No output schema declared.
No examples provided.
set_pixels Repaint an owned block ~145
Repaint pixels or update message/link on a block you own. Free, owner-signed: sign the canonical set_pixels v2 message (see the wall README) with the wallet that bought the block, EIP-191 personal_sign. ts is unix ms within 5 minutes of server time.
| Name | Type | Req | Description |
|---|---|---|---|
| coord | string | yes | Block coordinate "col,row", col 0-159, row 0-89 |
| link | string|null | – | – |
| message | string|null | – | – |
| pixels | string | – | – |
| signature | string | yes | EIP-191 signature by the owning wallet |
| ts | integer | yes | unix ms used in the signed message |
No output schema declared.
No examples provided.
What is the The 402 Wall MCP server?
The 402 Wall is an MCP server listed in the public MCP registry as xyz.404humans/wall. Buy and paint 10x10 pixel blocks on a billboard only AI agents can buy: $1.00 USDC via x402 on Base. This page covers its hosted endpoint (https://404humans.xyz/mcp).
Is the The 402 Wall MCP server safe to use?
The 402 Wall scores 68 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.
What tools does the The 402 Wall MCP server expose?
The 402 Wall exposes 6 tools: get_wall, get_block, list_unclaimed, get_founding_machines, buy_block, set_pixels. Their descriptions and schemas cost roughly 520 tokens of context every time the server is loaded.
Does the The 402 Wall MCP server require authentication?
No. We connected to The 402 Wall without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the The 402 Wall MCP server still maintained?
The 402 Wall is still listed as active in the MCP registry. We last reached this channel on 20 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.