{"uid":"cap_R6Xs56xE4uhnyxsXPiqSc","slug":"accelerometer-ai-progress-delta-feed-x402-0c819a16","name":"Accelerometer AI-Progress Delta Feed (x402)","description":"Readings of AI progress: dated snapshots of 129 public AI-progress and technology time series (frontier benchmark scores, compute trends, AGI prediction-market odds, model pricing, AI stocks and crypto, energy, space, robotics, biomed, research output), and the acceleration between any two readings. Paid with USDC on Base via x402.","url":"https://x402-accelerometer-feed.fly.dev/ai-progress/what-changed/%7Bfrom%7D/%7Bto%7D","method":"GET","headers":{},"bodySchema":{"type":"object","properties":{"properties":{"type":"string"}}},"responseSchema":{"type":"json","example":{"to":{"run_at":"2026-09-16T12:25:28.530204+00:00","snapshot_id":"2026-09-16"},"from":{"run_at":"2026-07-12T14:00:05.754191+00:00","snapshot_id":"2026-07-12"},"kind":"delta","n_moved":76,"sources":[{"id":"agents.x402_services_count","to":{"date":"2026-09-16","value":2865},"from":{"date":"2026-07-12","value":1779},"unit":"count","domain":"agents","metric":"x402 pay-per-request services (agentic.market)","delta_abs":1086,"delta_pct":61.0455,"new_observation":true},{"id":"autonomy.metr_time_horizon_50","to":{"date":"2025-04-16","value":112.230447},"from":{"date":"2025-04-16","value":112.230447},"unit":"minutes","domain":"autonomy","metric":"METR frontier task-completion horizon @50% (minutes)","delta_abs":0,"delta_pct":0,"new_observation":false}],"composite":null,"n_sources":129,"schema_version":"0.2"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","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":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_LuGJqb9grQ_nP-MKjVvjm","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns the change (delta) in 129 AI-progress and technology time series between two specified dates, paid via USDC on Base using x402.","exampleAgentPrompt":"Show me everything that changed in AI progress metrics between July 12 2026 and September 16 2026 — I want the deltas across all 129 series including benchmarks, compute, AGI prediction-market odds, and model pricing.","exampleUseCases":[{"title":"Quarterly AI acceleration report","prompt":"What changed most in AI progress between April 1 2026 and July 1 2026? Give me the biggest absolute and percentage movers across all 129 series — benchmarks, compute, pricing, prediction markets, everything."},{"title":"Tracking AGI odds and model pricing shift","prompt":"How much did AGI prediction-market odds and frontier model pricing shift between January 15 2026 and June 15 2026? Pull the delta snapshot for those two dates."},{"title":"Monitoring AI autonomy horizon growth","prompt":"I want to see how the METR frontier task-completion horizon metric changed between the snapshot from 2025-04-01 and the one from 2026-01-01 — show me the delta and whether it counts as a new observation."}],"resultDescription":"A JSON object containing the two snapshot timestamps (from/to), the kind field set to 'delta', the number of series that moved (n_moved), and an array of per-source entries each with absolute and percentage delta values, unit, domain label, metric name, and a new_observation flag. Also includes total n_sources (129) and schema version.","failureModes":["Invalid or malformed date strings in {from} or {to} path parameters return an error","Date outside available snapshot range returns no data or an empty delta","Payment failure or insufficient USDC balance on Base results in 402 payment required response","Network timeout from the fly.dev host may occur under load","Snapshot not yet generated for a future date returns an error or empty result"],"whenToPreferThis":"Choose this endpoint when you need to measure how much AI-progress metrics have changed between two specific dates rather than just viewing the current or historical state. It is the right choice for acceleration analysis, trend velocity measurement, and identifying which of the 129 tracked series moved the most over a given window. Prefer it over the snapshot endpoints when the question is 'what changed?' rather than 'what is the current value?'","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-20T12:30:07.771Z","isFirstParty":false}