ProofSlip
NPM · @PROOFSLIP/MCP-SERVER
Receipt-based verification for AI agent workflows — create, verify, and poll ephemeral proof objects
Available components
Last scanned (3 hours ago)
Scores higher than 65% of npm servers
Category Workflow Automation
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 Security81
- No malware found by supply-chain analysis.Pass
- CVE check failed: a known high-severity CVE affects zod 3.25.76, a direct dependency. A fixed version is available. View diagnostics → Fail
- No install/post-install scripts declared.Pass
- 30 of 93 dependencies flagged as unhealthy. View diagnostics → Partial
Provenance & Transparency45
- 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 214 days ago).Pass
- Disclosure check failed: no security disclosure policy was found in the source repository. See how to fix → Fail
Schema Quality & AI Usability81
- AI-judged instruction clarity (excellent).Pass
- Tool/resource definitions use about 477 tokens (~119/item across 4 items; 4 tools + 0 resources), lean.Pass
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management100
- No destabilizing schema changes in the last 30 days.Pass
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 4 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 4 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
Checks we ran (16)
- Malware scan
- Known CVEs
- Install scripts
- Dependency health
- Source repository
- Provenance
- License
- Maintenance
- Security disclosure
- Schema quality
- Stability
- Tool coverage
- Injection markers
- Destructive annotations
- Judged manipulation
- MCP protocol
Does not apply to this package (2)
- Endpoint SecurityScored on hosted endpoints only. A package has no live endpoint of its own for us to probe.
- Transport & ReachabilityScored on hosted endpoints only. A package has no live endpoint of its own for us to probe.
The score does not measure everything. What the score does not measure →
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.
- 4 Nov 26 +1
- Stability: 0.97 → pass security
- 2 Nov 26 −1
- Stability: pass → 0.93 functional
- 27 Oct 26 +1
- Stability: 0.97 → pass security
- 26 Oct 26 −1
- Stability: pass → 0.97 functional
- 24 Oct 26 −5
- CVE-2023-54404 affects this package: high ▼ security
- Known CVEs: pass → fail ▼ security
- 20 Oct 26 0
- Stability: 0.97 → pass security
- 19 Oct 26 0
- Stability: pass → 0.97 functional
- 17 Oct 26 +2
- Stability: 0.87 → pass security
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 6 Nov 2026 · Analysed npm/@proofslip/mcp-server@0.2.3
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 →
Vulnerabilities 1 finding
| ID | CVE | Severity | Vector | Fix available |
|---|---|---|---|---|
| GHSA-mrhx-c7xc-m3w5 | CVE-2023-54404 | high | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | yes |
Background: What a vulnerability scan can and cannot prove →
Dependencies 93 packages
| Packages resolved | 93 |
|---|---|
| Stale | 30 |
| 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 →
check_receipt_status ~95
Lightweight status poll for a ProofSlip receipt. Returns only status, is_terminal, and next_poll_after_seconds — no payload or summary. Use this instead of verify_receipt when you only need to know if a receipt state has changed. If is_terminal is false, wait next_poll_after_seconds before checking again. No API key required.
| Name | Type | Req | Description |
|---|---|---|---|
| receipt_id | string | yes | The receipt ID to check (starts with rct_) |
No output schema declared.
No examples provided.
create_receipt ~223
Create a ProofSlip receipt to record that something happened. Use 'action' for completed events, 'approval' for decisions awaiting review, 'handshake' for agent-to-agent coordination, 'resume' for continuation bookmarks, 'failure' for structured error records. Returns a receipt_id and verify_url. Receipts expire after 24 hours by default.
| Name | Type | Req | Description |
|---|---|---|---|
| audience | string | – | Set to "human" to enrich the verification page with social cards |
| expires_in | number | – | TTL in seconds (60-86400, default 86400 = 24 hours) |
| idempotency_key | string | – | Prevents duplicate receipts if you retry the same request |
| payload | object | – | Optional structured JSON data (max 4KB) |
| ref | object | – | Optional workflow reference IDs for tracing |
| status | string | yes | Freeform status string (e.g. "success", "pending", "failed") |
| summary | string | yes | Human-readable summary of what happened (max 280 chars) |
| type | string | yes | Receipt type |
No output schema declared.
No examples provided.
signup ~74
Get a free ProofSlip API key. Returns the key directly — save it immediately, it cannot be retrieved later. Only needed once. After signup, configure the key as PROOFSLIP_API_KEY environment variable to use create_receipt. Free tier: 500 receipts per month.
| Name | Type | Req | Description |
|---|---|---|---|
| string | yes | Your email address |
No output schema declared.
No examples provided.
verify_receipt ~85
Verify a ProofSlip receipt and retrieve its full data (type, status, summary, payload, ref, expiry). Use this to check what happened before deciding what to do next. Returns the complete receipt if valid, or a not_found error if expired or missing. No API key required.
| Name | Type | Req | Description |
|---|---|---|---|
| receipt_id | string | yes | The receipt ID to verify (starts with rct_) |
No output schema declared.
No examples provided.
How do I install the ProofSlip MCP server?
ProofSlip runs locally as an npm package, launched with npx -y @proofslip/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 · @proofslip/mcp-server
claude mcp add ai-proofslip-mcp-server -- npx -y @proofslip/mcp-server
What is the ProofSlip MCP server?
ProofSlip is an MCP server listed in the public MCP registry as ai.proofslip/mcp-server. Receipt-based verification for AI agent workflows, create, verify, and poll ephemeral proof objects. This page covers its npm package (@proofslip/mcp-server).
Is the ProofSlip MCP server safe to use?
ProofSlip scores 80 out of 100 on VerifyMCP. We recorded 1 known advisory against it as of 6 November 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 ProofSlip MCP server expose?
ProofSlip exposes 4 tools: create_receipt, verify_receipt, check_receipt_status, signup. Their descriptions and schemas cost roughly 477 tokens of context every time the server is loaded.
Is the ProofSlip MCP server still maintained?
ProofSlip is still listed as active in the MCP registry. We last reached this channel on 6 November 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 ProofSlip MCP server under?
ProofSlip declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.
What did VerifyMCP test on the ProofSlip MCP server?
VerifyMCP ran 16 checks on ProofSlip, covering Malware scan, Known CVEs, Install scripts, Dependency health and 12 more. Endpoint Security and Transport & Reachability do not apply to an npm package, so they were not tested. The score does not measure everything, and the scoring documentation lists what it leaves out.