Contribution Exchange
REMOTE · SIGNALAF.COM · SCANNED SEP 21
Contribution Exchange MCP: domain discovery, policies, preflight, proposals, and signals.
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 Security80
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- No authorisation is required to call this server. Every tool declares its destructiveHint and none is destructive, so open access doesn't expose one. See how to fix → View diagnostics → Partial
- HTTPS is enforced; there's no plaintext access path. View diagnostics → Pass
- The HSTS (Strict-Transport-Security) header is present. View diagnostics → Pass
- 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 Usability75
- AI-judged instruction clarity (excellent).Pass
- Context-footprint check failed: tool/resource definitions use about 966 tokens (~161/item across 6 items; 6 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 Management87
- Stability observed for 26 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage100
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 100% of tool parameters carry a description.Pass
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
Capabilities60
- Spec-recency check failed: implements MCP spec 2025-06-18; the latest is 2026-07-28. See how to fix → Fail
How do I install the Contribution Exchange MCP server?
Contribution Exchange is a hosted endpoint at https://signalaf.com/api/exchange/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 · signalaf.com
claude mcp add --transport http com-signalaf-contribution-exchange 'https://signalaf.com/api/exchange/mcp'
{
"mcpServers": {
"com-signalaf-contribution-exchange": {
"url": "https://signalaf.com/api/exchange/mcp"
}
}
} {
"servers": {
"com-signalaf-contribution-exchange": {
"type": "http",
"url": "https://signalaf.com/api/exchange/mcp"
}
}
} [mcp_servers.com-signalaf-contribution-exchange] url = "https://signalaf.com/api/exchange/mcp"
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"com-signalaf-contribution-exchange": {
"type": "remote",
"url": "https://signalaf.com/api/exchange/mcp",
"enabled": true
}
}
} openclaw mcp add com-signalaf-contribution-exchange --url 'https://signalaf.com/api/exchange/mcp' --transport streamable-http
mcp_servers:
com-signalaf-contribution-exchange:
url: "https://signalaf.com/api/exchange/mcp" {
"McpServers": {
"com-signalaf-contribution-exchange": {
"Transport": "http",
"Url": "https://signalaf.com/api/exchange/mcp"
}
}
} assistant mcp add com-signalaf-contribution-exchange -t streamable-http -u 'https://signalaf.com/api/exchange/mcp'
{
"mcpServers": {
"com-signalaf-contribution-exchange": {
"type": "http",
"url": "https://signalaf.com/api/exchange/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.
- 20 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 80 to 83. That category is still filling its 30-day observation window: 24 days of observed history at the previous scan, 25 at this one. The score rises as the window fills, whether or not the server changes.
- 18 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 73 to 77. That category is still filling its 30-day observation window: 22 days of observed history at the previous scan, 23 at this one. The score rises as the window fills, whether or not the server changes.
- 16 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 67 to 70. That category is still filling its 30-day observation window: 20 days of observed history at the previous scan, 21 at this one. The score rises as the window fills, whether or not the server changes.
- 14 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 60 to 63. That category is still filling its 30-day observation window: 18 days of observed history at the previous scan, 19 at this one. The score rises as the window fills, whether or not the server changes.
- 12 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.
- 10 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.
- 7 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 37 to 40. That category is still filling its 30-day observation window: 11 days of observed history at the previous scan, 12 at this one. The score rises as the window fills, whether or not the server changes.
- 5 Sept 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 30 to 33. That category is still filling its 30-day observation window: 9 days of observed history at the previous scan, 10 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 21 Sept 2026 · Probed https://signalaf.com/api/exchange/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=signalaf.com | CN=YR1,O=Let's Encrypt,C=US | 19 Aug 2026 | 17 Nov 2026 | RSA 2048 | SHA256-RSA | 5c4e742624ffd4d00250198ec01c5818860 |
| SANs: signalaf.com | ||||||
| CN=YR1,O=Let's Encrypt,C=US (CA) | CN=Root YR,O=ISRG,C=US | 3 Sept 2025 | 2 Sept 2028 | RSA 2048 | SHA256-RSA | a20253f15f2691c05dc1ce13b9bcca4e |
| CN=Root YR,O=ISRG,C=US (CA) | CN=ISRG Root X1,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | RSA 4096 | SHA256-RSA | f24b6d17f9d9ad7cb1c9fea78782699f |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of signalaf.com. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| com. | present | 19718 | 13 | Verified |
| signalaf.com. | 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 |
| Header | Value |
|---|---|
| strict-transport-security | max-age=63072000 |
| content-security-policy | default-src 'self'; script-src 'self' 'unsafe-inline' 'unsafe-eval' https://*.vercel-scripts.com https://www.googletagmanager.com; style-src 'self' 'unsafe-inline'; img-src 'self' data: https:; font-src 'self' data:; connect-src 'self' https://*.posthog.com https://*.supabase.co wss://*.supabase.co https://www.google-analytics.com https://*.google-analytics.com; frame-ancestors 'self' |
| x-content-type-options | nosniff |
| x-frame-options | SAMEORIGIN |
| referrer-policy | strict-origin-when-cross-origin |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://signalaf.com/api/exchange/mcp | Verified | 200 | |
| http (plaintext) | http://signalaf.com/api/exchange/mcp | HTTPS enforced | 308 | https://signalaf.com/api/exchange/mcp |
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 →
exchange_discover_domain Exchange Discover Domain — Contribution Exchange Profile Lookup ~124
Determine whether a domain publishes a Contribution Exchange profile. Returns the canonical Exchange manifest, policy URLs, signal URLs, and whether the domain is self-hosted or delegated to a Steward. Read-only — does not propose, commit, or authorize anything. Enforces HTTPS, redirect limits, timeouts, and SSRF protections (blocks loopback, link-local, private-network, and metadata-service targets).
| Name | Type | Req | Description |
|---|---|---|---|
| domain | string | yes | Domain name or HTTPS URL to check (e.g. 'signalaf.com' or 'https://signalaf.com'). Normalized to hostname. |
No output schema declared.
No examples provided.
exchange_get_attempt Exchange Get Attempt — Signal Attempt Detail ~82
Get detail for a signal attempt. Read-only. Enforces attempt visibility — actors may only read their own private attempts. Returns attempt status and verification result if available. Attempt status is NOT an exchange state. Verification is Steward-controlled and cannot be self-asserted.
| Name | Type | Req | Description |
|---|---|---|---|
| attempt_id | string | yes | Attempt ID. |
| signal_id | string | yes | Signal ID. |
No output schema declared.
No examples provided.
exchange_get_policy Exchange Get Policy — Domain Exchange Policy ~75
Fetch the canonical Contribution Exchange policy for a domain or its delegated Steward. Returns authority ceilings, consideration limits, human-review requirements, and supported behavior. Read-only — does not mutate state or perform preflight evaluation. Distinguishes a missing policy from an unavailable service.
| Name | Type | Req | Description |
|---|---|---|---|
| domain | string | yes | Domain name to fetch policy for. |
No output schema declared.
No examples provided.
exchange_get_signal Exchange Get Signal — Signal Detail by ID ~69
Get full detail for a single Exchange Signal by ID. Read-only. Returns the complete signal including constraints, participation rules, verification configuration, consideration declaration, and follow-on behavior. A signal does NOT create a Commitment, authorize execution, or guarantee payment.
| Name | Type | Req | Description |
|---|---|---|---|
| signal_id | string | yes | Signal ID. |
No output schema declared.
No examples provided.
exchange_list_signals Exchange List Signals — Domain-Published Work Signals ~234
List domain-published Exchange Signals (problems, requests, challenges, bounties, verification tasks, discoveries, experiments). Read-only. Returns canonical URLs, signal revision, revision hash, and status. Signal status is DISTINCT from exchange status — a signal does not create a Commitment or authorize execution. Supports the same filters and pagination as the HTTP API.
| Name | Type | Req | Description |
|---|---|---|---|
| accepting_attempts | boolean | – | Only return signals currently accepting attempts. |
| consideration_mode | string | – | Filter by consideration mode. |
| cursor | string | – | Pagination cursor from a previous response. |
| domain | string | – | Filter by publisher domain. |
| expires_before | string | – | ISO 8601 timestamp — only signals expiring before this. |
| label | string | – | Filter by label. |
| limit | integer | – | Maximum signals to return (1-100, default 50). |
| published_after | string | – | ISO 8601 timestamp — only signals published after this. |
| status | string | – | Filter by signal status. |
| type | string | – | Filter by signal type. |
| verification_mode | string | – | Filter by verification mode. |
No output schema declared.
No examples provided.
exchange_preflight Exchange Preflight — Advisory Proposal Policy Evaluation ~232
Evaluate a proposed contribution against the same policy logic used by the real proposal flow. Returns whether the proposal is likely to be auto-engaged, accepted for review, escalated to a human, or rejected as invalid. READ-ONLY: performs no proposal insertion, notification, event creation, or state transition. The result is advisory and time-bound — a favorable preflight does NOT guarantee engagement, Commitment, authorization, payment, or execution. Uses the same evaluateProposal function as the canonical proposal route.
| Name | Type | Req | Description |
|---|---|---|---|
| category | string | yes | Contribution category (e.g. 'technical', 'accessibility', 'documentation', 'research'). |
| confidence | object | – | Confidence in the observation (score 0-1 and basis). |
| consideration | array | – | Requested consideration (cash, royalty, reciprocal_access, attribution, referral, other). Advertised consideration is NOT binding until accepted through Commitment. |
| domain | string | yes | Target domain for the proposed contribution. |
| required_authorization | object | – | Authority requested (inspect_public, sandbox_test, repository_write, private_data, credential_access, production_modify, deploy, penetration_testing). |
No output schema declared.
No examples provided.
What is the Contribution Exchange MCP server?
Contribution Exchange is an MCP server listed in the public MCP registry as com.signalaf/contribution-exchange. Contribution Exchange MCP: domain discovery, policies, preflight, proposals, and signals. This page covers its hosted endpoint (https://signalaf.com/api/exchange/mcp).
Is the Contribution Exchange MCP server safe to use?
Contribution Exchange scores 84 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 Contribution Exchange MCP server expose?
Contribution Exchange exposes 6 tools: exchange_discover_domain, exchange_get_policy, exchange_preflight, exchange_list_signals, exchange_get_signal, exchange_get_attempt. Their descriptions and schemas cost roughly 816 tokens of context every time the server is loaded.
Does the Contribution Exchange MCP server require authentication?
No. We connected to Contribution Exchange without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the Contribution Exchange MCP server still maintained?
Contribution Exchange is still listed as active in the MCP registry. We last reached this channel on 21 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.