Perseus Ledger — verifiable, hash-chained event provenance
PYPI · PERSEUS-LEDGER · 2 COMPONENTS
Verifiable, hash-chained event provenance for autonomous systems. Local-first, MIT. 5 MCP tools.
Available components
Last scanned (17 hours ago)
Scores higher than 88% of PyPI servers
Category Monitoring and Observability
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
- Runs setuptools.build_meta at install time, a recognised build step with no custom scripting around it. View diagnostics → Pass
- 0 of 1 dependencies flagged as unhealthy. View diagnostics → Pass
Provenance & Transparency71
- Repository check failed: the declared repository URL returned HTTP 404. See how to fix → View diagnostics → Fail
- Cryptographically verified build provenance (signed, bound to Perseus-Computing-LLC/ledger). View diagnostics → Pass
- Clear OSI-approved license (MIT).Pass
- Actively maintained (last published 66 days ago).Pass
- Security-disclosure policy not yet verified: we couldn't inspect the source repository.Unverified
Schema Quality & AI Usability73
- AI-judged instruction clarity (good).Pass
- Context-footprint check failed: tool/resource definitions use about 644 tokens (~128/item across 5 items; 5 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 Coverage79
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 36% 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 5 captured tool definition(s), and no name or description among them implies an irreversible operation.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
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 +15
- Malware scan: unverified → pass ▲ security
- 15 Oct 26 −14
- Malware scan: pass → unverified ▼ security
- 14 Oct 26 +12
- Malware scan: unverified → pass ▲ security
- Stability: pass → 0.80 functional
- 13 Oct 26 −15
- Malware scan: pass → unverified ▼ security
- Stability: 0.97 → pass security
- 12 Oct 26 +16
- Malware scan: unverified → pass ▲ security
- 4 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 87 to 90. That category is still filling its 30-day observation window: 26 days of observed history at the previous scan, 27 at this one. The score rises as the window fills, whether or not the server changes.
- 2 Oct 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.
- 1 Oct 26 −3
- Stability: pass → 0.80 functional
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 16 Oct 2026 · Analysed pypi/perseus-ledger@1.2.4
Provenance Verified
A signed build attestation was found and verified, binding this exact artifact to the source repository it claims to come from.
| Result | Verified |
|---|---|
| Ecosystem | pypi |
| Reason | Verified |
| Discovered via | Registry attestation endpoint |
| Source repo | Perseus-Computing-LLC/ledger |
| Certificate issuer | https://token.actions.githubusercontent.com |
| Certificate SAN | https://github.com/Perseus-Computing-LLC/ledger/.github/workflows/release.yml@refs/tags/v1.2.4 |
| Rekor log index | 2411877798 |
| Predicate type | PyPI publish attestation https://docs.pypi.org/attestations/publish/v1 |
| Subject digest | sha256:53f5b0b8c2c7f789552bcf443d4e30dc5fd7eb3c78a8762ee98d22d1a31286a5 |
Background: How many MCP packages publish verified provenance →
Install scripts 1 script
| Hook | Tier | Command |
|---|---|---|
| build_backend | allowlisted | setuptools.build_meta |
Background: Why install scripts are a supply-chain risk →
Dependencies 1 package
| Packages resolved | 1 |
|---|---|
| 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 →
ledger_health ~28
Report the Ledger org, balance, workspace month-to-date spend, and provider health. Read-only.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
ledger_query ~76
List recent usage events for the org, newest first. Pass `before` (the `_rowid` of the last event from the previous page) to paginate. Read-only.
| Name | Type | Req | Description |
|---|---|---|---|
| before | integer | – | Cursor: rowid of the last event seen, for pagination. |
| limit | integer | – | Max events (1-500). |
No output schema declared.
No examples provided.
ledger_receipt ~117
Build a hash-only served-claim evidence receipt binding a source reference to a ledger event, with optional authority/provenance/scope/state context. Contains no prompts, memory bodies, or secrets. Read-only.
| Name | Type | Req | Description |
|---|---|---|---|
| authority_ref | string | – | – |
| event_ref | string | yes | Ledger event hash or external reference. |
| provenance_class | string | – | – |
| scope_anchor | string | – | – |
| source_ref | string | yes | Reference to the source being served (e.g. vault entity id). |
| state | string | – | – |
No output schema declared.
No examples provided.
ledger_record ~378
Meter one AI call: record provider/model/tokens/cost plus optional task, workspace, external ref, and action provenance into the hash-chained evidence ledger. Scoped write. Action-provenance fields (agent_id, authority_manifest_ref, scope_anchor, action_intent_hash, action_status, approval_ref) are all-or-nothing: supply all of them or none.
| Name | Type | Req | Description |
|---|---|---|---|
| action_intent_hash | string | – | – |
| action_receipt_hash | string | – | – |
| action_status | string | – | – |
| agent_id | string | – | Agent identity; required with the action-provenance set. |
| approval_ref | string | – | – |
| authority_manifest_ref | string | – | – |
| cache_read_tokens | integer | – | – |
| context_render_hash | string | – | – |
| context_render_schema | string | – | Required with any context-render evidence: context_render_hash, served_memory_provenance_hash, action_receipt_hash. |
| cost_usd | number | – | Exact cost in USD if known; estimated from pricing otherwise. |
| evidence_hashes | array | – | Hash-only evidence references (sha256 hex); hash-covered into the event. |
| external_ref | string | – | – |
| input_tokens | integer | – | – |
| model | string | – | – |
| output_tokens | integer | – | – |
| policy_version | string | – | – |
| provider | string | yes | Provider name (required), e.g. anthropic, openai, bedrock. |
| reasoning_tokens | integer | – | – |
| result_hash | string | – | Hash of the action result — never the result itself. |
| scope_anchor | string | – | – |
| served_memory_provenance_hash | string | – | Served-claim digest from a memory recall. |
| task_type | string | – | – |
| user_id | string | – | – |
| workspace | string | – | – |
No output schema declared.
No examples provided.
ledger_verify ~45
Walk the usage_events tamper-evidence hash chain and report divergences per org. Read-only.
| Name | Type | Req | Description |
|---|---|---|---|
| org | string | – | Org id or slug; all orgs if omitted. |
No output schema declared.
No examples provided.
How do I install the Perseus Ledger — verifiable, hash-chained event provenance MCP server?
Perseus Ledger — verifiable, hash-chained event provenance runs locally as a PyPI package, launched with uvx perseus-ledger. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
pypi · perseus-ledger
claude mcp add perseus-computing-llc-ledger -- uvx perseus-ledger
What is the Perseus Ledger — verifiable, hash-chained event provenance MCP server?
Perseus Ledger — verifiable, hash-chained event provenance is an MCP server listed in the public MCP registry as io.github.Perseus-Computing-LLC/ledger. Verifiable, hash-chained event provenance for autonomous systems. Local-first, MIT. 5 MCP tools. This page covers its PyPI package (perseus-ledger).
Is the Perseus Ledger — verifiable, hash-chained event provenance MCP server safe to use?
Perseus Ledger — verifiable, hash-chained event provenance scores 84 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 16 October 2026. Its build provenance is signed and verified. 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 Perseus Ledger — verifiable, hash-chained event provenance MCP server expose?
Perseus Ledger — verifiable, hash-chained event provenance exposes 5 tools: ledger_health, ledger_record, ledger_query, ledger_verify, ledger_receipt. Their descriptions and schemas cost roughly 644 tokens of context every time the server is loaded.
Is the Perseus Ledger — verifiable, hash-chained event provenance MCP server still maintained?
Perseus Ledger — verifiable, hash-chained event provenance is still listed as active in the MCP registry. We last reached this channel on 16 October 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 Perseus Ledger — verifiable, hash-chained event provenance MCP server under?
Perseus Ledger — verifiable, hash-chained event provenance declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.