io.github.WSattazahn/caveat-lang
NPM · CAVEAT-LANG
Authoring bridge for Caveat: validate, check and test programs; explain decisions; find dependents.
Available components
Last scanned (5 hours ago)
Scores higher than 96% of npm servers
Category Testing and QA
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
- No production dependencies, so there is no dependency health to assess. View diagnostics → Pass
Provenance & Transparency100
- Source repository is publicly reachable at the declared URL. View diagnostics → Pass
- Cryptographically verified build provenance (signed, bound to WSattazahn/caveat-lang). View diagnostics → Pass
- Clear OSI-approved license (MIT).Pass
- Actively maintained (last published 9 days ago).Pass
- Publishes a security disclosure policy (SECURITY.md).Pass
Schema Quality & AI Usability60
- AI-judged instruction clarity (excellent).Pass
- Context-footprint check failed: tool/resource definitions use about 1876 tokens (~375/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 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 5 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 6 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
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
No change was recorded against any check on this day. Stability & Change Management went from 90 to 93. That category is still filling its 30-day observation window: 27 days of observed history at the previous scan, 28 at this one. The score rises as the window fills, whether or not the server changes.
- 31 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 83 to 87. That category is still filling its 30-day observation window: 25 days of observed history at the previous scan, 26 at this one. The score rises as the window fills, whether or not the server changes.
- 28 Oct 26 +27
- Malware scan: unverified → pass ▲ security
- Known CVEs: unverified → pass ▲ security
- Dependency health: unverified → pass ▲ functional
- Package version: 0.1.0-rc.19 → 1.4.1 functional
- 27 Oct 26 −11
- Known CVEs: pass → unverified ▼ security
- Dependency health: pass → unverified ▼ functional
- Package version: 1.4.0 → 1.4.1 functional
- 26 Oct 26 −14
- Malware scan: pass → unverified ▼ security
- Security disclosure: fail → pass ▲ functional
- Package version: 1.3.0 → 1.4.0 functional
- 25 Oct 26 +16
- Malware scan: unverified → pass ▲ security
- 24 Oct 26 −15
- Malware scan: pass → unverified ▼ security
- Package version: 1.2.0 → 1.3.0 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 5 Nov 2026 · Analysed npm/caveat-lang@1.4.1
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 | npm |
| Reason | Verified |
| Discovered via | Registry attestation endpoint |
| Source repo | WSattazahn/caveat-lang |
| Certificate issuer | https://token.actions.githubusercontent.com |
| Certificate SAN | https://github.com/WSattazahn/caveat-lang/.github/workflows/publish-npm.yml@refs/tags/v1.4.1 |
| Rekor log index | 3499763513 |
| Predicate type | SLSA build provenance https://slsa.dev/provenance/v1 |
| Subject digest | sha512:f0cef95a96fc158e42e659229488fee49eef401ddaa0b9f03a811f8f176312c88805b5d6c9353d1a1abbcb67447102ec39a50e4cd8e82fdf169a4d6d6 |
Background: How many MCP packages publish verified provenance →
Dependencies 0 packages
| Packages resolved | 0 |
|---|---|
| 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 →
caveat_check ~300
Load a single-file program and report authoring diagnostics, such as repeated rules or a missing reopening path. Use after editing source; choose caveat_validate for a declaration summary and caveat_test for behavior assertions. A clean check does not prove behavior; bundles are unsupported. report (caveat-check/0.1) contains loads, strict, diagnostics and suppressed diagnostics, with code, location, message and suggestion, or a load error. exitCode: 0 completed without a strict failure; 1 strict with unsuppressed diagnostics; 2 load failure or bundle. Returns the same JSON in structuredContent and text: {schema:"caveat-authoring/0.1",operation,sourceSha256,runtime,exitCode,report}. Read exitCode even when isError is false. Bridge failures instead set isError:true with {schema:"caveat-authoring-error/0.1",error:{kind,message}}.
| Name | Type | Req | Description |
|---|---|---|---|
| source | string | yes | Complete inline Caveat program text, available as the virtual file inline.cav. No file path or URL lookup. At most 1 MiB of UTF-8 source; each call uses a fresh runtime. |
| strict | boolean | – | Optional, defaults to false. When true, any unsuppressed diagnostic makes exitCode 1 instead of 0; suppressed diagnostics do not count. Does not change program behavior. Load failures and unsupported… |
No output schema declared.
No examples provided.
caveat_dependents ~502
Replay optional events and find what rests on one named evidence item, reading stream or caveat. Use for impact inspection; caveat_explain instead explains all decisions and their reasons. Subjects are causes only: evidence, a reading stream or a caveat. Claims and decisions are never subjects, because a claim causes nothing and the grounds of a decision are evidence, not claims; both appear in the report as what the subject reaches. To trace from a claim, query the evidence that supports or opposes it (report.claims lists those relations). report (caveat-dependents/0.1) includes subject, kind, sequence, event outcomes, claims, decisions, changes, values, displayed values and withdrawal records; dependency entries distinguish grounds from possible influence through lineage. exitCode: 0 replay completed (may include rejected events); 1 fatal event with last good state; 2 load failure or unknown subject, with report.error. Returns the same JSON in structuredContent and text: {schema:"caveat-authoring/0.1",operation,sourceSha256,runtime,exitCode,report}. Read exitCode even when isError is false. Bridge failures instead set isError:true with {schema:"caveat-authoring-error/0.1",error:{kind,message}}.
| Name | Type | Req | Description |
|---|---|---|---|
| events | array | – | Events replayed in array order from a fresh session. Omitted or [] inspects the initial state; previous calls supply no history. Rejections are recorded and replay continues; a fatal event stops repl… |
| source | string | yes | Complete inline Caveat program text, available as the virtual file inline.cav. No file path or URL lookup. At most 1 MiB of UTF-8 source; each call uses a fresh runtime. |
| subject | string | yes | Exact case-sensitive evidence name, reading stream name, caveat name, or evidence occurrence ID after replay. Evidence records supplied observations; a reading stream is a named history of samples; a… |
No output schema declared.
No examples provided.
caveat_explain ~320
Replay optional events and explain the resulting decisions, evidence and displayed values. Use to answer why a decision was made; choose caveat_dependents to trace one evidence or caveat name forward, and caveat_test for assertions. report (caveat-explain/0.1) includes sequence, event outcomes, decisions with grounds and revision history, evidence with caveats, displayed values and available archive history. exitCode: 0 replay completed (may include rejected events); 1 fatal event with last good state; 2 source load failure (report has loads:false and error). Returns the same JSON in structuredContent and text: {schema:"caveat-authoring/0.1",operation,sourceSha256,runtime,exitCode,report}. Read exitCode even when isError is false. Bridge failures instead set isError:true with {schema:"caveat-authoring-error/0.1",error:{kind,message}}.
| Name | Type | Req | Description |
|---|---|---|---|
| events | array | – | Events replayed in array order from a fresh session. Omitted or [] inspects the initial state; previous calls supply no history. Rejections are recorded and replay continues; a fatal event stops repl… |
| source | string | yes | Complete inline Caveat program text, available as the virtual file inline.cav. No file path or URL lookup. At most 1 MiB of UTF-8 source; each call uses a fresh runtime. |
No output schema declared.
No examples provided.
caveat_test ~511
Run scenario assertions and runtime invariant checks against inline source, with a fresh session per scenario. Use to verify expected event outcomes and snapshot values; caveat_validate only checks loading, caveat_check reports diagnostics, and caveat_explain inspects history without assertions. report (caveat-scenario-report/0.1) includes files, per-scenario results/failures, check diagnostics and passed/failed totals. exitCode: 0 all passed; 1 scenario failure; 2 invalid scenario document (report has valid:false and error) or blocking authoring diagnostics. Every source reference must be inline.cav. Returns the same JSON in structuredContent and text: {schema:"caveat-authoring/0.1",operation,sourceSha256,runtime,exitCode,report}. Read exitCode even when isError is false. Bridge failures instead set isError:true with {schema:"caveat-authoring-error/0.1",error:{kind,message}}.
| Name | Type | Req | Description |
|---|---|---|---|
| scenarios | object | yes | Scenario document object, not JSON text. Example: {"schema":"caveat-scenarios/0.1","source":"inline.cav","scenarios":[{"id":"initial","title":"Initial sequence","steps":[{"expect":{"/sequence":0}}]}]… |
| source | string | yes | Complete inline Caveat program text, available as the virtual file inline.cav. No file path or URL lookup. At most 1 MiB of UTF-8 source; each call uses a fresh runtime. |
No output schema declared.
No examples provided.
caveat_validate ~218
Load inline source with the installed runtime and list its declarations. Start here to find load errors; use caveat_check for authoring diagnostics and caveat_test to verify expected behavior. No events are dispatched. report (caveat-validate/0.1) contains program, loads, events, reading_streams, decision_series and displayed bindings, or a load error. exitCode: 0 loaded; 2 load failure. Returns the same JSON in structuredContent and text: {schema:"caveat-authoring/0.1",operation,sourceSha256,runtime,exitCode,report}. Read exitCode even when isError is false. Bridge failures instead set isError:true with {schema:"caveat-authoring-error/0.1",error:{kind,message}}.
| Name | Type | Req | Description |
|---|---|---|---|
| source | string | yes | Complete inline Caveat program text, available as the virtual file inline.cav. No file path or URL lookup. At most 1 MiB of UTF-8 source; each call uses a fresh runtime. |
No output schema declared.
No examples provided.
How do I install the io.github.WSattazahn/caveat-lang MCP server?
io.github.WSattazahn/caveat-lang runs locally as an npm package, launched with npx -y caveat-lang mcp. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.
npm · caveat-lang
claude mcp add wsattazahn-caveat-lang -- npx -y caveat-lang mcp
What is the io.github.WSattazahn/caveat-lang MCP server?
io.github.WSattazahn/caveat-lang is an MCP server listed in the public MCP registry as io.github.WSattazahn/caveat-lang. Authoring bridge for Caveat: validate, check and test programs; explain decisions; find dependents. This page covers its npm package (caveat-lang).
Is the io.github.WSattazahn/caveat-lang MCP server safe to use?
io.github.WSattazahn/caveat-lang scores 93 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 5 November 2026. It declares no install or post-install scripts. 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 io.github.WSattazahn/caveat-lang MCP server expose?
io.github.WSattazahn/caveat-lang exposes 5 tools: caveat_validate, caveat_check, caveat_test, caveat_explain, caveat_dependents. Their descriptions and schemas cost roughly 1,851 tokens of context every time the server is loaded.
Is the io.github.WSattazahn/caveat-lang MCP server still maintained?
io.github.WSattazahn/caveat-lang is still listed as active in the MCP registry. We last reached this channel on 5 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 io.github.WSattazahn/caveat-lang MCP server under?
io.github.WSattazahn/caveat-lang 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 io.github.WSattazahn/caveat-lang MCP server?
VerifyMCP ran 16 checks on io.github.WSattazahn/caveat-lang, 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.