{"uid":"cap_yc_IMhSIqhNSS32dZDhmP","slug":"aimarket-mcp-tool-diff-mcp-diff-50f99220","name":"AIMarket MCP Tool Diff (mcp-diff)","description":"MCP security: catch a rug pull or tool poisoning between two tools/list results of the same MCP server — the version you approved and the one it serves now. Flags instructions aimed at the model, override and concealment wording, credential and wallet paths, covert actions, hidden Unicode, new URLs and addresses, a dropped readOnlyHint, new command or path parameters and look-alike tool names; verdict unchanged, changed, review or suspicious, with a word diff per changed tool.","url":"https://modelmarket.dev/x402/mcp-diff?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"new":{"type":"array","description":"the server's current tools/list result"},"old":{"type":"array","description":"the approved tools/list result (a list of tools, or {tools})"}}},"responseSchema":{"type":"json","example":{"result":{},"status":"ok","receipt":{},"service":"mcp-diff","capability_id":"mcp.tools.diff@v1"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.003","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.003/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_XMZvhhpBALD-8MAVDfd75","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.003","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Compares two versions of an MCP server's tools/list to detect tool poisoning, rug pulls, hidden instructions, and other security-relevant changes between an approved and currently-served toolset.","exampleAgentPrompt":"Before connecting to this MCP server, compare the tools/list I approved last week with what it's serving right now and tell me if anything suspicious changed — look for hidden instructions, new wallet paths, dropped readOnlyHints, or look-alike tool names.","exampleUseCases":[{"title":"Catching tool poisoning before agent execution","prompt":"I'm about to let my agent use this MCP server — can you diff the tools/list I approved yesterday against what the server is returning right now and flag anything that looks like a rug pull or injected instruction?"},{"title":"Auditing MCP server update for hidden changes","prompt":"The MCP server I use just pushed an update. Compare the old tool definitions I saved with the new ones and highlight any changes involving credential paths, wallet addresses, or wording that tries to override my agent's behavior."},{"title":"Continuous integrity check in agentic pipeline","prompt":"Run a security diff between my last-approved MCP tools/list snapshot and the current one — I need a verdict of unchanged, changed, review, or suspicious, plus a word diff for every tool that's different."}],"resultDescription":"A JSON result containing a verdict (unchanged, changed, review, or suspicious), a word-level diff for each changed tool showing exactly what was added or removed, and flagged findings covering hidden Unicode, prompt-injection wording, new URLs or wallet addresses, dropped readOnlyHint, new command/path parameters, and look-alike tool names. Also includes a payment receipt and capability_id.","failureModes":["Malformed or missing 'old'/'new' arrays returns a validation error","Empty arrays produce an 'unchanged' verdict with no diff","Server unreachable or payment failure returns an x402 or 5xx error","Very large tool lists may time out or exceed payload limits","Subtle Unicode obfuscation that passes diff may not be caught if it uses novel encoding"],"whenToPreferThis":"Use this endpoint when you need to verify that an MCP server's tools have not been tampered with between your approval step and runtime — specifically to catch tool poisoning, rug pulls, prompt injection, or hidden instructions injected into tool descriptions. Prefer this over manual inspection or generic diff tools because it applies MCP-specific security heuristics (readOnlyHint, look-alike names, credential paths, hidden Unicode) and returns a machine-readable verdict that an agent pipeline can act on automatically.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-10T06:32:43.750Z","isFirstParty":false,"canonicalSlug":"aimarket-mcp-tool-diff-mcp-diff-50f99220"}