{
  "schema": "varexis-public-evidence-record/0.3",
  "generated_at_utc": "2026-10-13T23:52:59.204Z",
  "record_id": "VXI-EXT-TOOL-TRUST-CLICKHOUSE-01-v1",
  "record_kind": "external_reference",
  "title": "ClickHouse MCP: Read-only defaults and write opt-ins",
  "system": "ClickHouse MCP",
  "evidence_family": "agent_tool_trust_review",
  "index_status": "PUBLIC_SAFE_SOURCE_REVIEW",
  "evidence_state": "PRIMARY_DOCUMENTATION_REVIEW_ONLY",
  "canonical_question": "What evidence separates an analytical ClickHouse MCP session from one that may alter data?",
  "near_questions": [
    "Is ClickHouse MCP read-only by default?",
    "Can enabling ClickHouse MCP writes override database restrictions?",
    "What additional control applies to destructive ClickHouse operations?",
    "Is chDB enabled in my ClickHouse MCP configuration?",
    "Which database user does ClickHouse MCP use?",
    "Does database authentication protect the MCP listener itself?",
    "Can a ClickHouse agent inspect schemas without writes?",
    "What should I verify before allowing an INSERT through MCP?",
    "Where can ClickHouse query results be copied by an assistant?",
    "Does an old ClickHouse review cover new write settings?",
    "What evidence distinguishes analytical and mutating ClickHouse access?",
    "What triggers another ClickHouse MCP configuration review?"
  ],
  "supported_claims": [
    {
      "claim": "The ClickHouse MCP documentation describes read-only queries by default, an explicit write-access opt-in and an additional destructive-operation control. Database restrictions still apply. Review the effective settings and whether embedded chDB is enabled before making a claim about the session boundary.",
      "reliance": "DOCUMENTED_CAPABILITY_ONLY"
    }
  ],
  "not_demonstrated_claims": [
    "Verified buyer configuration or effective access rights",
    "Independent execution, completeness or security testing",
    "Vendor certification, legal compliance or guaranteed suitability"
  ],
  "public_summary": "The ClickHouse MCP documentation describes read-only queries by default, an explicit write-access opt-in and an additional destructive-operation control. Database restrictions still apply. Review the effective settings and whether embedded chDB is enabled before making a claim about the session boundary.",
  "related_record_ids": [
    "VXI-EXT-TOOL-TRUST-MONGODB-01-v1",
    "VXI-EXT-TOOL-TRUST-SNOWFLAKE-01-v1",
    "VXI-EXT-TOOL-TRUST-QDRANT-01-v1",
    "VXI-EXT-TOOL-TRUST-PINECONE-01-v1",
    "VXI-EXT-TOOL-TRUST-REDIS-01-v1"
  ],
  "source_review": {
    "source_type": "official_external_documentation",
    "source_title": "ClickHouse MCP read-only and write controls",
    "source_url": "https://github.com/ClickHouse/mcp-clickhouse",
    "checked_on": "2026-10-14",
    "candidate_record_id": "VXI-EXT-TOOL-TRUST-CLICKHOUSE-01-v1",
    "candidate_record_sha256": "5e151f82a4e2a0b969e94dfcedd2d0bbeb5dfadf0260bc4006230682544d5812",
    "method": "Primary documentation reviewed for the published bounded statement.",
    "deployment_tested_by_varexis": false,
    "revalidation": "The delivered snapshot preserves the review date shown. Recheck current primary documentation and deployment context before relying on present applicability; payment does not trigger fresh research."
  },
  "answer_policy": {
    "classification": "DOCUMENTED_WITH_DEPLOYMENT_BOUNDARY",
    "bounded_answer": "The ClickHouse MCP documentation describes read-only queries by default, an explicit write-access opt-in and an additional destructive-operation control. Database restrictions still apply. Review the effective settings and whether embedded chDB is enabled before making a claim about the session boundary.",
    "required_buyer_context": "Server version, ClickHouse credentials, database policy, write settings and any enabled chDB backend.",
    "missing_evidence": "A broader claim needs evidence matching the intended use. Payment does not upgrade the evidence state."
  },
  "private_boundary": "Raw logs, thresholds, private paths, source code, protected mechanisms and reconstruction-level details are excluded from public and paid delivery.",
  "trust_profile": {
    "schema": "varexis-agent-tool-trust/1",
    "identity": {
      "tool": "ClickHouse MCP",
      "variant": "Official ClickHouse/mcp-clickhouse; remote ClickHouse and optional embedded chDB configuration"
    },
    "review_status": "documentation_review_only",
    "checked_on": "2026-10-14",
    "version_scope": "Dated rolling documentation snapshot; no installed or hosted runtime version independently verified.",
    "plan_scope": "Buyer plan, entitlement and effective configuration are not verified.",
    "findings": [
      {
        "field": "operator",
        "label": "Publisher and operator",
        "status": "documented",
        "statement": "ClickHouse publishes the MCP server; deployment configuration belongs to the operator.",
        "source_ids": [
          "clickhouse-main"
        ]
      },
      {
        "field": "purpose",
        "label": "Purpose",
        "status": "documented",
        "statement": "The server supports data exploration through ClickHouse and optional embedded chDB.",
        "source_ids": [
          "clickhouse-main"
        ]
      },
      {
        "field": "reads",
        "label": "Read capability",
        "status": "documented",
        "statement": "Database and table discovery and analytical queries are exposed.",
        "source_ids": [
          "clickhouse-main"
        ]
      },
      {
        "field": "writes",
        "label": "Write capability",
        "status": "documented",
        "statement": "Writes require explicit enablement; destructive operations have an additional documented opt-in.",
        "source_ids": [
          "clickhouse-main"
        ]
      },
      {
        "field": "auth",
        "label": "Authentication",
        "status": "documented",
        "statement": "Connection credentials identify the database user; MCP transport authentication is separately configured.",
        "source_ids": [
          "clickhouse-main"
        ]
      },
      {
        "field": "permissions",
        "label": "Permission surface",
        "status": "documented",
        "statement": "Default query mode is read-only and database restrictions continue to constrain enabled writes.",
        "source_ids": [
          "clickhouse-main"
        ]
      },
      {
        "field": "egress",
        "label": "Data leaving the environment",
        "status": "review_inference",
        "statement": "Results reach the client; optional local backends change which data environment the tool accesses.",
        "source_ids": [
          "clickhouse-main"
        ]
      },
      {
        "field": "failures",
        "label": "Failure modes to consider",
        "status": "review_inference",
        "statement": "A stale review may miss newly enabled writes or a second backend.",
        "source_ids": [
          "clickhouse-main"
        ]
      },
      {
        "field": "unknown",
        "label": "Unknowns and applicability",
        "status": "unknown",
        "statement": "Database grants, effective environment settings, transport exposure and installed version are unverified.",
        "source_ids": []
      },
      {
        "field": "gate",
        "label": "Suggested refusal or clarification condition",
        "status": "varexis_review_policy",
        "statement": "Confirm the backend and effective write policy before describing a connection as analysis-only.",
        "source_ids": []
      }
    ],
    "evidence_sources": [
      {
        "source_id": "clickhouse-main",
        "url": "https://github.com/ClickHouse/mcp-clickhouse",
        "final_url": "https://github.com/ClickHouse/mcp-clickhouse",
        "title": "ClickHouse MCP read-only and write controls",
        "checked_on": "2026-10-14",
        "sha256": "96e86095087c5e24505ab422b668a3bf58c6537e9a240755c7fc8111ba4ccabb",
        "bytes": 644509
      }
    ],
    "observed_tool_execution": false,
    "policy_basis": "Suggested VAREXIS review gates; apply the buyer's authorized task and policy. These conditions do not execute or enforce controls.",
    "commercial_reliance_boundary": "A source-linked review aid, not a vendor certification, security clearance or deployment assessment. Unknown does not mean false or unsafe.",
    "paid_value": {
      "decision_context": "Preserve the configuration assumptions that keep analytical access distinct from data changes.",
      "free": "Complete review, practical questions, sources and limitations; may be saved locally.",
      "single_request": "Existing server-saved version-bound route snapshot for later authenticated retrieval.",
      "evidence_receipt": "The same snapshot plus the existing unsigned delivery receipt.",
      "excluded": [
        "Fresh vendor research",
        "Continuous monitoring or change alerts",
        "Testing the buyer configuration",
        "Private evidence or vendor certification"
      ],
      "integrity": "Hashes identify content versions; they do not prove truth or provide a signature."
    },
    "revalidation": {
      "trigger": "Recheck when permissions, deployment, authentication, source guidance or intended use changes; a purchase does not trigger revalidation.",
      "specific_watch": "Recheck write flags, destructive-operation controls, backends and database identity."
    },
    "change_history": [
      {
        "version": 1,
        "date": "2026-10-14",
        "change": "Initial documentation review; no earlier vendor assessment claimed."
      }
    ]
  },
  "paid_access_note": "The full published answer and boundaries are free. Paid access saves the selected route and source versions, with an unsigned receipt when purchased. Preview coverage before paying. Fresh research, bespoke assessment and protected evidence are excluded.",
  "service_route": {
    "request_guide": "/varexis-index/request.html",
    "request_workflow": "/varexis-index/request-workflow.json",
    "service_id": "single_request",
    "service_routes_url": "/varexis-index/service-routes.json",
    "payment_required": true,
    "availability_endpoint": "/api/index/capabilities",
    "operational_status": "AUTOMATIC_SERVICE_CAPABILITIES_GATED",
    "checkout_url": "/index-access"
  },
  "authority_boundary": "VAREXIS-INDEX informs evidence reliance. It does not provide advice, certification, deployment authority, security assurance, production approval, or guarantee.",
  "human_page": "/varexis-index/catalog.html#clickhouse-mcp-write-optin-trust",
  "machine_readable_record": "/varexis-index/records/clickhouse-mcp-write-optin-trust.json"
}
