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Chamber

NPM · JSON-CHAMBER-MCP · SCANNED SEP 20

Two-key JSON seal/open. Cloak needs a live license. Open is keys-only.

Available components

67 Trust /100
Trust breakdown (7 categories)

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 Security98
  • 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
  • 31 of 95 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 (AGPL-3.0-or-later).Pass
  • Actively maintained (last published 5 days ago).Pass
  • Disclosure check failed: no security disclosure policy was found in the source repository. See how to fix → Fail
Schema Quality & AI Usability62
  • AI-judged instruction clarity (fair).Partial
  • Tool/resource definitions use about 186 tokens (~37/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 Management0
  • Stability not yet verified: not enough scan history yet (needs a 30-day window).Unverified
Tool Coverage93
  • 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
  • 80% 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
Capabilities100
  • Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass

Unverified: 1 category

A category scored 0 because we could not verify it: a data source with nothing on this package, evidence we could not reach, or a check we could not run. We only credit what we can confirm.

Install

How do I install the Chamber MCP server?

Chamber runs locally as an npm package, launched with npx -y json-chamber-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 · json-chamber-mcp

# add to Claude Code
claude mcp add ceedot-rock-json-chamber-mcp -- npx -y json-chamber-mcp
// .cursor/mcp.json
{
  "mcpServers": {
    "ceedot-rock-json-chamber-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "json-chamber-mcp"
      ]
    }
  }
}
// .vscode/mcp.json
{
  "servers": {
    "ceedot-rock-json-chamber-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "json-chamber-mcp"
      ]
    }
  }
}
# add to Codex CLI
codex mcp add ceedot-rock-json-chamber-mcp -- npx -y json-chamber-mcp
// opencode.json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "ceedot-rock-json-chamber-mcp": {
      "type": "local",
      "command": [
        "npx",
        "-y",
        "json-chamber-mcp"
      ],
      "enabled": true
    }
  }
}
# add to OpenClaw
openclaw mcp add ceedot-rock-json-chamber-mcp --command npx --arg -y --arg json-chamber-mcp
# ~/.hermes/config.yaml
mcp_servers:
  ceedot-rock-json-chamber-mcp:
    command: "npx"
    args: ["-y", "json-chamber-mcp"]
// ~/.netclaw/config/netclaw.json
{
  "McpServers": {
    "ceedot-rock-json-chamber-mcp": {
      "Transport": "stdio",
      "Command": "npx",
      "Arguments": [
        "-y",
        "json-chamber-mcp"
      ]
    }
  }
}
# add to Vellum
assistant mcp add ceedot-rock-json-chamber-mcp -t stdio -c npx -a -y json-chamber-mcp
// mcp.json
{
  "mcpServers": {
    "ceedot-rock-json-chamber-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "json-chamber-mcp"
      ]
    }
  }
}
Changelog

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.

  • 15 Sept 26 +15
    • Malware scan: unverified → pass security
  • 14 Sept 26 52

    First indexed and scored.

Diagnostics

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 20 Sept 2026 · Analysed npm/json-chamber-mcp@1.2.0

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 95 packages
Packages resolved 95
Stale 31
Tree resolution Complete

Background: SBOMs and build attestations, explained →

MCP tools · 5 exposed · ~186 tokens

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 →

Tool Tokens
benefit_check ~49

Entropy + bias gate for $1900 tier. Always available. No TRU8.

NameTypeReqDescription
datastringyesUTF-8 text or base64 binary
encodingstring

No output schema declared.

No examples provided.

chamber_cloak ~53

Seal JSON/text with φ-split + AES-256-GCM. Requires live license.

NameTypeReqDescription
datastringyesJSON string or plain text
is_jsonbooleanValidate as JSON (default true)

No output schema declared.

No examples provided.

chamber_info ~27

Package info, cloak license ($9/mo · $99/yr), open is keys-only.

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

chamber_open ~37

Open a sealed chamber blob. Keys only — no license, no clock.

NameTypeReqDescription
sealedobjectyesSealed blob from chamber_cloak

No output schema declared.

No examples provided.

chamber_status ~20

License status: eval remaining hours, purchased, or dead.

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

Common questions

What is the Chamber MCP server?

Chamber is an MCP server listed in the public MCP registry as io.github.ceedot-rock/json-chamber-mcp. Two-key JSON seal/open. Cloak needs a live license. Open is keys-only. This page covers its npm package (json-chamber-mcp).

Is the Chamber MCP server safe to use?

Chamber scores 67 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 20 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 Chamber MCP server expose?

Chamber exposes 5 tools: chamber_status, chamber_info, chamber_cloak, chamber_open, benefit_check. Their descriptions and schemas cost roughly 186 tokens of context every time the server is loaded.

Is the Chamber MCP server still maintained?

Chamber is still listed as active in the MCP registry. We last reached this channel on 20 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 Chamber MCP server under?

Chamber declares the AGPL-3.0-or-later licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.