Sprucelab — the complete, unedited output of the deterministic mcptrustchecker engine v1.9.0, scanned . Every finding, capability tag and score component below is exactly what the engine produced — no AI, no post-processing.
{
"tool": {
"name": "mcptrustchecker",
"version": "1.9.0",
"methodologyVersion": "mcptrustchecker-1.9"
},
"target": {
"id": "sprucelab",
"source": {
"kind": "package",
"origin": "sprucelab"
},
"server": {
"name": "sprucelab"
}
},
"grade": "B",
"score": {
"score": 88,
"threatScore": 100,
"grade": "B",
"band": "B",
"categorySubtotals": {
"injection": 0,
"exfiltration": 0,
"permissions": 0,
"supply-chain": 0,
"network": 0,
"hygiene": 0
},
"vector": [
{
"kind": "client",
"term": "capability-exposure",
"level": "critical",
"label": "capability blast radius (critical) — client exposure if the model is manipulated",
"appliedPenalty": 10
},
{
"kind": "client",
"term": "verification-discount",
"level": "none",
"label": "publisher verification (unlinked) — no provenance/repo link, but the shipped source was fully read",
"appliedPenalty": 2
},
{
"kind": "client",
"term": "coverage-honesty",
"level": "source",
"label": "inspection depth (source) — how much of the target the scan could see",
"appliedPenalty": 0
}
],
"gatesFired": [],
"methodologyVersion": "mcptrustchecker-1.9"
},
"capability": {
"level": "critical",
"reasons": [
"ingests untrusted external content (a prompt-injection entry point)",
"can send data / act on an external service",
"reads sensitive or local data",
"has a read → egress path (a data-exfiltration surface)",
"can execute shell commands or code",
"untrusted-input, sensitive-source and egress co-exist across tools (toxic-flow surface)",
"untrusted input can reach code execution"
],
"tags": [
"untrusted-input",
"external-sink",
"sensitive-source",
"code-exec"
]
},
"coverage": {
"level": "source",
"inputs": {
"toolSurface": true,
"implementationSource": true,
"packageMetadata": true,
"liveTransport": false
},
"caveats": [
"Tools were statically extracted from the published source (50 recovered), not enumerated from a running server. Tool-poisoning, Unicode-smuggling, capability and toxic-flow analysis ran on this inferred surface, but a mis-parsed registration could be missed or mis-attributed, so tool-derived findings are capped below “confirmed”. To grade the real runtime surface, scan the running server: --command \"npx -y <package>\"."
]
},
"findings": [
{
"ruleId": "MTC-FLOW-002",
"title": "Completed toxic-flow trifecta across tools",
"category": "exfiltration",
"severity": "critical",
"confidence": "strong",
"description": "This server (without client built-ins) exposes a complete data-exfiltration chain: agent_tools_manifest → list_files → capabilities. Untrusted input is ingested, private data is read, and it can be sent to an external sink via the agent composing the tools (→). Static analysis proves the primitive exists, not that a specific run will occur.",
"remediation": "Remove one leg of the trifecta: isolate untrusted-input tools from secret-reading tools and from egress tools, or require human approval between them.",
"location": {
"kind": "flow",
"name": "agent_tools_manifest → list_files → capabilities"
},
"owasp": "LLM02:2025 Sensitive Information Disclosure",
"references": [],
"data": {
"untrusted": [
"capabilities",
"agent_tools_manifest",
"eir_catalog",
"eir_presets"
],
"sources": [
"list_files"
],
"sinks": [
"capabilities",
"create_issue",
"upload_file",
"create_webhook",
"disable_webhook",
"delete_webhook",
"test_webhook"
],
"path": [
"agent_tools_manifest",
"list_files",
"capabilities"
],
"edges": [
{
"from": "agent_tools_manifest",
"to": "list_files",
"kind": "agent-mediated"
},
{
"from": "list_files",
"to": "capabilities",
"kind": "agent-mediated"
}
],
"wired": false
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in server code (sprucelab/cli/dev.py)",
"category": "permissions",
"severity": "high",
"confidence": "strong",
"description": "In the server's implementation (`sprucelab/cli/dev.py:74`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "sprucelab/cli/dev.py"
},
"evidence": ".py\", *args] return subprocess.run( cmd, cwd=_backend_dir(), capture_output=capture,",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "sprucelab/cli/dev.py",
"line": 74,
"nonRuntime": false
}
},
{
"ruleId": "MTC-SRC-002",
"title": "Shell/command execution in packaging/dev tooling (tests/test_mcp_entrypoint.py)",
"category": "permissions",
"severity": "low",
"confidence": "heuristic",
"description": "In a packaging/dev/install script (shipped, but not the server runtime) (`tests/test_mcp_entrypoint.py:32`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "tests/test_mcp_entrypoint.py"
},
"evidence": "<args>``.\"\"\" return subprocess.run( [sys.executable, *ENTRY_MODULE, *args], capture_output=True,",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-002",
"file": "tests/test_mcp_entrypoint.py",
"line": 32,
"nonRuntime": true
}
},
{
"ruleId": "MTC-SRC-005",
"title": "Dynamic module load from a non-literal in packaging/dev tooling (tests/conftest.py)",
"category": "permissions",
"severity": "low",
"confidence": "heuristic",
"description": "In a packaging/dev/install script (shipped, but not the server runtime) (`tests/conftest.py:77`): Loading a module chosen at runtime (from a variable) can pull in and run attacker-influenced code paths. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.",
"remediation": "Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.",
"location": {
"kind": "server",
"name": "tests/conftest.py"
},
"evidence": "y: module = __import__(dotted, fromlist=[\"console\"]) except ImportError: continue",
"owasp": "LLM05:2025 Improper Output Handling",
"data": {
"rule": "MTC-SRC-005",
"file": "tests/conftest.py",
"line": 77,
"nonRuntime": true
}
},
{
"ruleId": "MTC-SUP-012",
"title": "Package has no license",
"category": "hygiene",
"severity": "info",
"confidence": "strong",
"description": "\"sprucelab\" has no declared license. This is a legal/reuse concern, not a security finding.",
"location": {
"kind": "package",
"name": "sprucelab"
}
},
{
"ruleId": "MTC-SUP-011",
"title": "Package declares no source repository",
"category": "supply-chain",
"severity": "info",
"confidence": "strong",
"description": "\"sprucelab\" declares no repository URL, so its published artifact cannot be compared against reviewable source.",
"remediation": "Prefer packages that link to public, reviewable source.",
"location": {
"kind": "package",
"name": "sprucelab"
}
}
],
"toxicFlows": [
{
"id": "flow-1",
"severity": "critical",
"confidence": "strong",
"untrustedInput": [
"capabilities",
"agent_tools_manifest",
"eir_catalog",
"eir_presets"
],
"sensitiveSource": [
"list_files"
],
"externalSink": [
"capabilities",
"create_issue",
"upload_file",
"create_webhook",
"disable_webhook",
"delete_webhook",
"test_webhook"
],
"selfContained": false,
"path": [
"agent_tools_manifest",
"list_files",
"capabilities"
],
"pathWired": false,
"description": "A cross-tool exfiltration chain exists: agent_tools_manifest → list_files → capabilities."
}
],
"capabilities": [
{
"tool": "capabilities",
"tags": [
"untrusted-input",
"external-sink"
],
"reasons": {
"untrusted-input": [
"keyword \"fetch\""
],
"external-sink": [
"keyword \"webhook\""
]
}
},
{
"tool": "agent_tools_manifest",
"tags": [
"untrusted-input"
],
"reasons": {
"untrusted-input": [
"keyword \"fetch\""
]
}
},
{
"tool": "list_projects",
"tags": [],
"reasons": {}
},
{
"tool": "eir_catalog",
"tags": [
"untrusted-input"
],
"reasons": {
"untrusted-input": [
"keyword \"fetch\""
]
}
},
{
"tool": "eir_presets",
"tags": [
"untrusted-input"
],
"reasons": {
"untrusted-input": [
"keyword \"fetch\""
]
}
},
{
"tool": "scaffold_project",
"tags": [],
"reasons": {}
},
{
"tool": "list_models",
"tags": [],
"reasons": {}
},
{
"tool": "list_types",
"tags": [],
"reasons": {}
},
{
"tool": "verify_dry_run",
"tags": [],
"reasons": {}
},
{
"tool": "verify_model",
"tags": [],
"reasons": {}
},
{
"tool": "classify_types",
"tags": [],
"reasons": {}
},
{
"tool": "list_issues",
"tags": [],
"reasons": {}
},
{
"tool": "create_issue",
"tags": [
"external-sink"
],
"reasons": {
"external-sink": [
"keyword \"create_issue\""
]
}
},
{
"tool": "update_issue",
"tags": [],
"reasons": {}
},
{
"tool": "issues_from_verification",
"tags": [],
"reasons": {}
},
{
"tool": "list_scopes",
"tags": [],
"reasons": {}
},
{
"tool": "create_scope",
"tags": [],
"reasons": {}
},
{
"tool": "list_files",
"tags": [
"sensitive-source"
],
"reasons": {
"sensitive-source": [
"keyword \"list_files\""
]
}
},
{
"tool": "list_observations",
"tags": [],
"reasons": {}
},
{
"tool": "show_project",
"tags": [],
"reasons": {}
},
{
"tool": "list_members",
"tags": [],
"reasons": {}
},
{
"tool": "add_member",
"tags": [],
"reasons": {}
},
{
"tool": "remove_member",
"tags": [],
"reasons": {}
},
{
"tool": "mint_tenant_token",
"tags": [],
"reasons": {}
},
{
"tool": "list_tenant_tokens",
"tags": [],
"reasons": {}
},
{
"tool": "revoke_tenant_token",
"tags": [],
"reasons": {}
},
{
"tool": "eir_rules",
"tags": [],
"reasons": {}
},
{
"tool": "eir_apply_preset",
"tags": [],
"reasons": {}
},
{
"tool": "eir_add_rule",
"tags": [],
"reasons": {}
},
{
"tool": "eir_remove_rule",
"tags": [],
"reasons": {}
},
{
"tool": "eir_set_rules",
"tags": [],
"reasons": {}
},
{
"tool": "show_file",
"tags": [],
"reasons": {}
},
{
"tool": "upload_file",
"tags": [
"external-sink"
],
"reasons": {
"external-sink": [
"keyword \"upload_file\""
]
}
},
{
"tool": "reprocess_file",
"tags": [],
"reasons": {}
},
{
"tool": "extraction_log",
"tags": [],
"reasons": {}
},
{
"tool": "show_issue",
"tags": [],
"reasons": {}
},
{
"tool": "resolve_issue",
"tags": [],
"reasons": {}
},
{
"tool": "list_webhooks",
"tags": [],
"reasons": {}
},
{
"tool": "create_webhook",
"tags": [
"external-sink"
],
"reasons": {
"external-sink": [
"keyword \"webhook\""
]
}
},
{
"tool": "disable_webhook",
"tags": [
"external-sink"
],
"reasons": {
"external-sink": [
"keyword \"webhook\""
]
}
},
{
"tool": "delete_webhook",
"tags": [
"external-sink"
],
"reasons": {
"external-sink": [
"keyword \"webhook\""
]
}
},
{
"tool": "list_deliveries",
"tags": [],
"reasons": {}
},
{
"tool": "redeliver",
"tags": [],
"reasons": {}
},
{
"tool": "test_webhook",
"tags": [
"external-sink"
],
"reasons": {
"external-sink": [
"keyword \"webhook\""
]
}
},
{
"tool": "list_claims",
"tags": [],
"reasons": {}
},
{
"tool": "get_claim",
"tags": [],
"reasons": {}
},
{
"tool": "promote_claim",
"tags": [],
"reasons": {}
},
{
"tool": "reject_claim",
"tags": [],
"reasons": {}
},
{
"tool": "supersede_claim",
"tags": [],
"reasons": {}
},
{
"tool": "claim_conflicts",
"tags": [],
"reasons": {}
}
],
"surfaceDigest": "1f6883955acbd4d15307173145c989a56b75f7951f8b067ca76939c7c9789e11",
"stats": {
"tools": 50,
"prompts": 0,
"resources": 0,
"findingsBySeverity": {
"critical": 1,
"high": 1,
"medium": 0,
"low": 2,
"info": 2
}
}
}