# Receipt — sign an agent's work, verify it offline (mcpb · ggbank-receipt.mcpb)

Ed25519 receipts over work artifacts: issue and verify offline, no account, no chain, no network.

- Trust score: 47/100 (low)
- Change this week: +3
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-11-05

## Components

- remote · `receipt.whirlwindcorp.com`: 62/100, [markdown](https://verifymcp.io/servers/ecstatica-ggbank-receipt/receipt.md), [page](https://verifymcp.io/servers/ecstatica-ggbank-receipt/receipt)
- mcpb · `ggbank-receipt.mcpb`: 47/100 (this document), [markdown](https://verifymcp.io/servers/ecstatica-ggbank-receipt/ggbank-receipt.md), [page](https://verifymcp.io/servers/ecstatica-ggbank-receipt/ggbank-receipt)

## Channel facts

- Registry: `mcpb`
- Package: `https://github.com/ecstatica/ggbank-receipt/releases/download/v1.0.0/ggbank-receipt.mcpb`
- Transport: `stdio`
- SHA-256: `17ac189297b705462caf4af5330810632e791697ceaeba00e26398d1adfc42d8`

## Trust breakdown

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. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-11-05.

- **Supply Chain Security**: 13/100
  - No malware scan is available for this kind of package: the supply-chain vendors we use do not cover it. This is a permanent gap in our coverage, not a finding about the package.
  - Known CVEs were checked across the 4 of 4 dependencies we could resolve, so this covers what we could see, not the whole tree.
  - Install-script risk not yet assessed.
  - 0 of 4 dependencies flagged as unhealthy.
- **Provenance & Transparency**: 45/100
  - Source repository is publicly reachable at the declared URL.
  - Provenance check failed: no build-provenance attestation is published.
  - Clear OSI-approved license (MIT).
  - Actively maintained (last published 6 days ago).
  - Disclosure check failed: no security disclosure policy was found in the source repository.
- **Schema Quality & AI Usability**: 72/100
  - AI-judged instruction clarity (good).
  - Tool/resource definitions use about 178 tokens (~89/item across 2 items; 2 tools + 0 resources), lean.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 23/100
  - Stability observed for 7 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - We read all 2 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 2 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.

## Install

### How do I install the Receipt — sign an agent's work, verify it offline MCP server?

Receipt — sign an agent's work, verify it offline ships as an MCPB bundle, a single file you download and open in an MCP host that supports MCPB bundles, such as Claude Desktop. The host reads the launch command from the bundle's own manifest, so there is no command to copy. Before opening it, check the file's SHA-256 matches the one the MCP registry declares for it, 17ac189297b705462caf4af5330810632e791697ceaeba00e26398d1adfc42d8; the commands to do that are on this page. If it does not match, do not open it.

- Download bundle: `https://github.com/ecstatica/ggbank-receipt/releases/download/v1.0.0/ggbank-receipt.mcpb`
- SHA-256: `17ac189297b705462caf4af5330810632e791697ceaeba00e26398d1adfc42d8`

### Verify on macOS / Linux

```bash
echo "17ac189297b705462caf4af5330810632e791697ceaeba00e26398d1adfc42d8  ggbank-receipt.mcpb" | shasum -a 256 -c
```

### Verify on Windows (PowerShell)

```powershell
(Get-FileHash -Algorithm SHA256 .\ggbank-receipt.mcpb).Hash -eq "17ac189297b705462caf4af5330810632e791697ceaeba00e26398d1adfc42d8"
```

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-11-04 (score 47, +1)

No change was recorded against any check on this day. Stability & Change Management went from 17 to 20. That category is still filling its 30-day observation window: 5 days of observed history at the previous scan, 6 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-11-02 (score 46, +1)

No change was recorded against any check on this day. Stability & Change Management went from 10 to 13. That category is still filling its 30-day observation window: 3 days of observed history at the previous scan, 4 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-31 (score 45, +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.

### 2026-10-29 (score 44)

First indexed and scored.

## MCP tools (2)

### `issue_receipt` (~116 tokens)

Sign an artifact with an Ed25519 receipt. Returns the receipt JSON: artifact hash, agent, task, amount and a signature anyone can verify offline.

Input parameters:

- `agent` (string, required): agent identifier, e.g. VOID-9
- `amount_gg` (number): amount paid for the work
- `artifact_path` (string, required): path to the delivered file
- `key_path` (string): optional Ed25519 private key file; a fresh key is used otherwise
- `task` (string, required): task or quest id

### `verify_receipt` (~62 tokens)

Verify a receipt offline: signature, every field, and optionally the artifact hash. Returns ok=false with the failing reason when anything has changed.

Input parameters:

- `artifact_path` (string): optional file to hash-check
- `receipt` (object, required): the receipt object as issued

## Diagnostics

Captured diagnostic sections: Provenance, Dependencies. The full working is on the page: https://verifymcp.io/servers/ecstatica-ggbank-receipt/ggbank-receipt#diagnostics

## Score history

- 2026-11-05: 47
- 2026-11-04: 47
- 2026-11-03: 46
- 2026-11-02: 46
- 2026-11-01: 45
- 2026-10-31: 45
- 2026-10-30: 44
- 2026-10-29: 44

## Common questions

### What is the Receipt — sign an agent's work, verify it offline MCP server?

Receipt — sign an agent's work, verify it offline is an MCP server listed in the public MCP registry as io.github.ecstatica/ggbank-receipt. Ed25519 receipts over work artifacts: issue and verify offline, no account, no chain, no network. This page covers its MCPB bundle (https://github.com/ecstatica/ggbank-receipt/releases/download/v1.0.0/ggbank-receipt.mcpb).

### Is the Receipt — sign an agent's work, verify it offline MCP server safe to use?

Receipt — sign an agent's work, verify it offline scores 47 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 Receipt — sign an agent's work, verify it offline MCP server expose?

Receipt — sign an agent's work, verify it offline exposes 2 tools: issue_receipt, verify_receipt. Their descriptions and schemas cost roughly 178 tokens of context every time the server is loaded.

### What licence is the Receipt — sign an agent's work, verify it offline MCP server under?

Receipt — sign an agent's work, verify it offline declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.

## Links

- Repository: https://github.com/ecstatica/ggbank-receipt
- Changelog RSS feed: https://verifymcp.io/servers/ecstatica-ggbank-receipt/ggbank-receipt.xml
- Changelog JSON feed: https://verifymcp.io/servers/ecstatica-ggbank-receipt/ggbank-receipt.json
- HTML version of this page: https://verifymcp.io/servers/ecstatica-ggbank-receipt/ggbank-receipt