{"uid":"cap_oQ0XNmYAOIxS-FwNIIBDi","slug":"signalharness-prompt-version-compare-d8868710","name":"SignalHarness Prompt Version Compare","description":"Explore 330 pay-per-call x402 API services and 27 agent-native digital products, with Base USDC pricing, secure Polar checkout, and free discovery.","url":"https://signalharness.ai/api/agent/services/prompt_version_compare/invoke","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"request_json":{"type":"string","maxLength":65536,"minLength":2}}},"responseSchema":{"type":"json","example":{"replay":false,"result":{"warnings":["Verify the caller-supplied data before relying on this result."],"service_id":"prompt_version_compare","analysis_json":"{\"example\":\"schema-valid caller-supplied data\"}","evidence_scope":"caller_supplied_data"},"status":"succeeded","receipt":{"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","usage":[],"status":"succeeded","network":"eip155:8453","artifacts":[],"endedAtMs":0,"latencyMs":0,"paymentId":"example-payment","receiptId":"example-receipt","requestId":"example-request","serviceId":"prompt_version_compare","executionId":"example-execution","startedAtMs":0,"amountAtomic":"15000","resultSha256":"a26d9692763c1b62d563885c3ade30c7377e84fcb8f58b032a2f3cee2fd35e82","serviceVersion":"1.0.0","settlementReference":"0x0000000000000000000000000000000000000000000000000000000000000000"},"artifacts":[],"requestId":"example-request","executionId":"example-execution"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.015","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":"$0.015/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.015","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.015","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_dJVpK511cLnZdfHo8Zjtl","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.015","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Compares two or more versions of an LLM prompt to analyze differences, regressions, or improvements across prompt iterations","exampleAgentPrompt":"Compare these two prompt versions for me and tell me what changed and which looks stronger: version 1 is 'You are a helpful assistant. Answer questions concisely.' and version 2 is 'You are an expert assistant. Provide thorough, step-by-step answers with examples.'","exampleUseCases":[{"title":"Pre-deployment prompt regression check","prompt":"Before I ship this prompt update to production, compare my old prompt 'Summarize the following text in 3 bullet points.' with my new version 'Provide a concise 3-bullet summary, highlighting the most actionable insights.' and tell me if there are any regressions or concerns."},{"title":"Iterative prompt improvement audit","prompt":"I've been iterating on my customer support prompt — can you compare version A: 'Help the user resolve their issue politely.' with version B: 'You are a friendly support agent. Empathize with the user, then offer a clear resolution in under 100 words.' and break down what's meaningfully different?"},{"title":"Prompt A/B test analysis","prompt":"I'm running an A/B test on my RAG system prompts. Compare prompt variant 1: 'Answer based only on the provided context.' versus variant 2: 'Using only the context below, answer the question. If unsure, say so.' — which one is more precise and why?"}],"resultDescription":"Returns a JSON analysis object containing a comparison of the supplied prompt versions, any warnings about the caller-supplied data, the service ID, and a signed receipt with payment metadata including amount, network, and result hash for auditability.","failureModes":["Malformed or invalid request_json causes validation error","Prompt version data missing or too short (minLength:2 not met)","Payload exceeds 65536 character limit causing rejection","Insufficient USDC balance for the $0.015 per-call fee","Analysis may reflect only caller-supplied data with no external ground truth — results carry a verification warning"],"whenToPreferThis":"Choose this endpoint when you need a structured, paid, auditable comparison of LLM prompt versions — especially in agent pipelines where you want a receipt-backed result with a result hash for verification. Prefer this over manual diffing or free tools when you need programmatic JSON output with auditability, or when operating in an x402 micropayment workflow on Base.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T19:01:32.240Z","isFirstParty":false}