ContractGate
NPM · @CONTRACTGATE/MCP-SERVER · SCANNED SEP 25
Infer, dry-run, deploy, and inspect ContractGate semantic data contracts.
Available components
How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, and we only credit what we can confirm. How we score → Why this is hard to score →
Supply Chain Security100
- No malware found by supply-chain analysis.Pass
- No known CVEs affecting this package version or its production dependencies.Pass
- No install/post-install scripts declared.Pass
- 0 of 3 dependencies flagged as unhealthy. View diagnostics → Pass
Provenance & Transparency48
- Source repository is publicly reachable at the declared URL. View diagnostics → Pass
- Provenance check failed: no build-provenance attestation is published. See how to fix → View diagnostics → Fail
- Clear OSI-approved license (MIT).Pass
- Actively maintained (last published 7 days ago).Pass
- Publishes a security disclosure policy (SECURITY.md).Pass
Schema Quality & AI Usability84
- 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).Pass
- AI-judged instruction clarity (good).Pass
- Tool/resource definitions use about 443 tokens (~88/item across 5 items; 5 tools + 0 resources), lean.Pass
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management27
- Stability observed for 8 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage98
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 93% 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
- All 1 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation.Pass
- An AI judge read all 5 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a current MCP spec version (2026-07-28).Pass
How do I install the ContractGate MCP server?
ContractGate runs locally as an npm package, launched with npx -y @contractgate/mcp-server. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
npm · @contractgate/mcp-server
claude mcp add nightmoose-contractgate -- npx -y @contractgate/mcp-server
{
"mcpServers": {
"nightmoose-contractgate": {
"command": "npx",
"args": [
"-y",
"@contractgate/mcp-server"
]
}
}
} {
"servers": {
"nightmoose-contractgate": {
"command": "npx",
"args": [
"-y",
"@contractgate/mcp-server"
]
}
}
} codex mcp add nightmoose-contractgate -- npx -y @contractgate/mcp-server
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"nightmoose-contractgate": {
"type": "local",
"command": [
"npx",
"-y",
"@contractgate/mcp-server"
],
"enabled": true
}
}
} openclaw mcp add nightmoose-contractgate --command npx --arg -y --arg @contractgate/mcp-server
mcp_servers:
nightmoose-contractgate:
command: "npx"
args: ["-y", "@contractgate/mcp-server"] {
"McpServers": {
"nightmoose-contractgate": {
"Transport": "stdio",
"Command": "npx",
"Arguments": [
"-y",
"@contractgate/mcp-server"
]
}
}
} assistant mcp add nightmoose-contractgate -t stdio -c npx -a -y @contractgate/mcp-server
{
"mcpServers": {
"nightmoose-contractgate": {
"command": "npx",
"args": [
"-y",
"@contractgate/mcp-server"
]
}
}
} 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.
- 25 Sept 26 +3
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 17 Sept 26 73
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 25 Sept 2026 · Analysed npm/@contractgate/mcp-server@0.1.2
Provenance No attestation
The registry publishes no build provenance for this version, so there is nothing to verify.
| Result | No attestation |
|---|---|
| Ecosystem | npm |
Background: How many MCP packages publish verified provenance →
Dependencies 3 packages
| Packages resolved | 3 |
|---|---|
| Tree resolution | Complete |
Background: SBOMs and build attestations, explained →
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 →
deploy_contract Deploy a contract to stable ~118
POST /contracts/deploy — find-or-create by name, insert YAML as stable, deprecate prior stable. 409 if that (name, version) exists: bump version in the YAML. Refused while quarantine is pending. Save the returned contract_id.
| Name | Type | Req | Description |
|---|---|---|---|
| deployed_by | string | – | Actor recorded on the version row |
| name | string | yes | Contract name matching the YAML name: field |
| source | string | – | Logical feed name, e.g. app-backend |
| yaml_content | string | yes | Full contract YAML |
No output schema declared.
No examples provided.
get_quarantine List quarantined events ~63
GET /quarantine — rejected events for the caller's org, newest first, with violation details.
| Name | Type | Req | Description |
|---|---|---|---|
| contract_id | string | – | Restrict to one contract |
| limit | integer | – | Default 100, max 500 |
| offset | integer | – | – |
No output schema declared.
No examples provided.
infer_contract Infer a contract from sample events ~90
Generate draft ContractGate YAML from real JSON sample events via POST /contracts/infer. Does not persist. Review and write the YAML to contracts/<name>.yaml before deploying.
| Name | Type | Req | Description |
|---|---|---|---|
| description | string | – | Optional contract description |
| name | string | yes | Contract name, snake_case, e.g. user_events |
| samples | array | yes | 1–20 real event objects. Do not invent them. |
No output schema declared.
No examples provided.
list_contracts List contracts ~20
GET /contracts — identities the API key can see.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
validate_events Validate events against a contract ~152
Validate events. Pass contract_id to hit POST /v1/ingest/{id} (dry_run defaults true — no audit, quarantine, or usage). Pass yaml_content to hit POST /playground/validate per event (never persists). Exactly one of contract_id or yaml_content. 207/422 responses are returned as data so you can apply each violation's suggestion.
| Name | Type | Req | Description |
|---|---|---|---|
| contract_id | string | – | Deployed contract UUID from deploy_contract |
| dry_run | boolean | – | Ingest only. Default true. Set false only after a successful dry run. |
| events | array | yes | Event objects to validate |
| yaml_content | string | – | In-flight contract YAML; uses the playground, never persists |
No output schema declared.
No examples provided.
What is the ContractGate MCP server?
ContractGate is an MCP server listed in the public MCP registry as io.github.nightmoose/contractgate. Infer, dry-run, deploy, and inspect ContractGate semantic data contracts. This page covers its npm package (@contractgate/mcp-server).
Is the ContractGate MCP server safe to use?
ContractGate scores 76 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 25 September 2026. It declares no install or post-install scripts. 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 ContractGate MCP server expose?
ContractGate exposes 5 tools: infer_contract, validate_events, deploy_contract, get_quarantine, list_contracts. Their descriptions and schemas cost roughly 443 tokens of context every time the server is loaded.
Is the ContractGate MCP server still maintained?
ContractGate is still listed as active in the MCP registry. We last reached this channel on 25 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.
What licence is the ContractGate MCP server under?
ContractGate declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.