Surface Contract: how platform APIs really behave
REMOTE · PENNY-SURFACE-CONTRACT.PENNY-MCAMP.WORKERS.DEV
Evidence-cited machine-readable contracts for how agent platform APIs really behave
Available components
Last scanned (51 minutes ago)
Scores higher than 45% of remote servers
Reachable. Last reached 18 Oct 2026.
Category Developer Tools
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 7 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 404, 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 Usability65
- AI-judged instruction clarity (good).Pass
- Context-footprint check failed: tool/resource definitions use about 1177 tokens (~168/item across 7 items; 7 tools + 0 resources), over budget; trim descriptions and params. See how to fix → Fail
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management13
- Stability observed for 4 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage88
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 64% 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 7 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 8 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities60
- Spec-recency check failed: implements MCP spec 2025-06-18; the latest is 2026-07-28. See how to fix → Fail
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.
- 16 Oct 26 +1
- The server rewrote its instructions, which are the text every model session reads security
- Tool “contribute_discrepancy” rewrote its description, which is the text the model reads security
- Schema quality: pass → fail ▼ functional
- Tool coverage: 40% → 64% ▲ functional
- New tool “prepay_check” functional
- “contribute_discrepancy” added an optional parameter “observedAt” cosmetic
- “contribute_discrepancy” added an optional parameter “reporter” cosmetic
- “contribute_discrepancy” reworded the description of “contractId” cosmetic
- 15 Oct 26 +1
- The server rewrote its instructions, which are the text every model session reads security
- Schema quality: 64 → 107 ▼ functional
- Tool coverage: 25% → 40% ▲ functional
- Stability: unverified → 0.03 ▲ functional
- New tool “preflight_mcp_server” functional
- 14 Oct 26 55
First indexed and scored.
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 18 Oct 2026 · Probed https://penny-surface-contract.penny-mcamp.workers.dev/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=penny-mcamp.workers.dev | CN=YE2,O=Let's Encrypt,C=US | 9 Oct 2026 | 7 Jan 2027 | ECDSA 256 | ECDSA-SHA384 | 6fc0325c9744806cd5334a6d52db98ea060 |
| SANs: *.penny-mcamp.workers.dev, penny-mcamp.workers.dev | ||||||
| CN=YE2,O=Let's Encrypt,C=US (CA) | CN=Root YE,O=ISRG,C=US | 3 Sept 2025 | 2 Sept 2028 | ECDSA 384 | ECDSA-SHA384 | 4df3b15dd6c0784c507cd37b58e6f115 |
| CN=Root YE,O=ISRG,C=US (CA) | CN=ISRG Root X2,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | ECDSA 384 | ECDSA-SHA384 | 872165fc34b6e5fba8add5b3705fb53a |
| CN=ISRG Root X2,O=Internet Security Research Group,C=US (CA) | CN=ISRG Root X1,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | ECDSA 384 | SHA256-RSA | 6c8f1dc727c7117f7baf853ac980f9cd |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of penny-surface-contract.penny-mcamp.workers.dev. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| dev. | present | 60074 | 8 | Verified |
| workers.dev. | 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://penny-surface-contract.penny-mcamp.workers.dev/mcp | Verified | 200 | |
| http (plaintext) | http://penny-surface-contract.penny-mcamp.workers.dev/mcp | Inconclusive | 404 |
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 →
contribute_discrepancy ~318
Report a platform behaviour that contradicts a published claim, or a new claim, with evidence. One-line call: POST /v1/contribute with {contractId, kind, statement, evidence[], reporter, observedAt}. Stored as pending; a published contract is never changed without independent verification. A contractId no published contract serves is accepted as a NEW-PLATFORM PROPOSAL: the 202 body carries contractExists:false (with proposal:true, proposedContractId and proposedHost), it is listed distinctly at GET /v1/contributions, and it stays pending until a second party reproduces it - it never creates or mutates a contract. A proposal filed by us reads selfProbe:true in that listing, and GET /v1/contributions counts proposals filed by non-self submitters separately from our own self-probes, so only the non-self number is outside coverage.
| Name | Type | Req | Description |
|---|---|---|---|
| claimId | string | – | – |
| contractId | string | yes | the platform's contract id or host; an id no published contract serves is accepted as a new-platform proposal (contractExists:false) |
| evidence | array | yes | – |
| kind | string | yes | – |
| observedAt | string | – | ISO 8601 date you observed the behaviour; a claim without a date is not a measurement |
| reporter | string | – | your agent or operator name, so the record is attributed to you and is not read as one of ours (an unattributed record is counted non-self AND flagged noReporter) |
| statement | string | yes | – |
No output schema declared.
No examples provided.
get_integration_recipe ~77
Get a plain-text integration recipe for a platform: the order of operations to use it, and a guard clause for every behaviour we measured going wrong, each naming the contract claim behind it. Derived from the contract, so it cannot drift from it.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | contract id or host, e.g. moltbook |
No output schema declared.
No examples provided.
get_surface_contract ~75
Get the machine-readable surface contract for a platform host (read/write semantics, pending states, rate limits, limits, idempotency, pagination completeness, data portability), each claim carrying its evidence and its verification status.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | contract id or host, e.g. moltbook or www.moltbook.com |
No output schema declared.
No examples provided.
list_surface_contracts ~26
List the platform surface contracts published in Penny's free registry, with claim counts.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
preflight_mcp_server ~252
Run the anonymous MCP handshake against ANY https MCP endpoint you name, right now, and get back a verdict (open / refused / unreachable / initialize-transport-error), the shape of any refusal body, whether the server is stateful (sets Mcp-Session-Id), how many tools tools/list returns, and the guard clauses that follow. Use it before wiring an MCP server into your own config. Pass `urls` (up to 5) to check a whole mcp.json in one call. When the endpoint refuses, it also reports whether the refusal advertises a credential path (an RFC 9728 resource_metadata pointer) and whether that pointer resolves to a metadata document naming an authorization server, so you learn where a token would come from without writing that parsing yourself. No credential is sent, none is obtained, and none of their tools is ever called.
| Name | Type | Req | Description |
|---|---|---|---|
| url | string | – | absolute https URL of the MCP endpoint, e.g. https://host/mcp |
| urls | array | – | batch form: 2 to 5 absolute https URLs, checked with the same battery in one call (each one counts against the same daily egress budget as a single preflight) |
No output schema declared.
No examples provided.
prepay_check ~237
Check an x402 route BEFORE you pay it. GET /v1/prepay?url=<the route> makes ONE unpaid GET with no payment header and no credential, and returns one row: the measured HTTP status, the parsed x402 v2 challenge (scheme / network / asset / amount / payTo), whether that challenge is schema-valid exact-on-Base, and whether its payTo and price agree with the seller's own card (pass `card` to read that card with one more unpaid GET). No payment is made, no credential is sent, no redirect is followed, and a transport failure on our side is reported as unknown rather than as a fact about the seller. Use it to gate a payment decision on measured terms instead of on a seller's prose.
| Name | Type | Req | Description |
|---|---|---|---|
| card | string | – | optional: absolute https URL of the seller's own card/listing page, read with one more unpaid GET to compare the wallet and the price it advertises (agreement is true|false|unknown, and unknown is nu… |
| url | string | yes | absolute https URL of the route you are about to pay |
No output schema declared.
No examples provided.
verify_surface ~39
Run the anonymous conformance checks for a contract now and return verified / failed / unknown / manual / unsupported per claim.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | – |
No output schema declared.
No examples provided.
How do I install the Surface Contract: how platform APIs really behave MCP server?
Surface Contract: how platform APIs really behave is a hosted endpoint at https://penny-surface-contract.penny-mcamp.workers.dev/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 · penny-surface-contract.penny-mcamp.workers.dev
claude mcp add --transport http dev-workers-penny-mcamp-penny-surface-contract-s 'https://penny-surface-contract.penny-mcamp.workers.dev/mcp'
What is the Surface Contract: how platform APIs really behave MCP server?
Surface Contract: how platform APIs really behave is an MCP server listed in the public MCP registry as dev.workers.penny-mcamp.penny-surface-contract/surface-cont…. Evidence-cited machine-readable contracts for how agent platform APIs really behave. This page covers its hosted endpoint (https://penny-surface-contract.penny-mcamp.workers.dev/mcp).
Is the Surface Contract: how platform APIs really behave MCP server safe to use?
Surface Contract: how platform APIs really behave scores 57 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 Surface Contract: how platform APIs really behave MCP server expose?
Surface Contract: how platform APIs really behave exposes 7 tools: list_surface_contracts, get_surface_contract, verify_surface, contribute_discrepancy, get_integration_recipe, and 2 more. Their descriptions and schemas cost roughly 1,024 tokens of context every time the server is loaded.
Does the Surface Contract: how platform APIs really behave MCP server require authentication?
No. We connected to Surface Contract: how platform APIs really behave without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the Surface Contract: how platform APIs really behave MCP server still maintained?
Surface Contract: how platform APIs really behave is still listed as active in the MCP registry. We last reached this channel on 18 October 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.