{"meta":{"version":"pdf-text-v1","kind":"example","free":true,"url":"https://bitcoin.org/bitcoin.pdf","asOf":"2026-09-02T20:11:11.166Z","cacheHit":false,"generatedInMs":1003,"note":"Free sample — a real /pdf/text extraction (text capped at 6000 chars here; the paid call returns up to 500,000). Your own document costs $0.01."},"pricing":{"/pdf/text":{"usd":0.01,"returns":"full extracted text of any public text-based PDF (no OCR)"}},"usage":"GET /pdf/text?url=","url":"https://bitcoin.org/bitcoin.pdf","bytes":184292,"pages":9,"chars":21228,"truncated":false,"likely_scanned":false,"text":"Bitcoin: A Peer-to-Peer Electronic Cash System\nSatoshi Nakamoto\nsatoshin@gmx.com\nwww.bitcoin.org\nAbstract. A purely peer-to-peer version of electronic cash would allow online\npayments to be sent directly from one party to another without going through a\nfinancial institution. Digital signatures provide part of the solution, but the main\nbenefits are lost if a trusted third party is still required to prevent double-spending.\nWe propose a solution to the double-spending problem using a peer-to-peer network.\nThe network timestamps transactions by hashing them into an ongoing chain of\nhash-based proof-of-work, forming a record that cannot be changed without redoing\nthe proof-of-work. The longest chain not only serves as proof of the sequence of\nevents witnessed, but proof that it came from the largest pool of CPU power. As\nlong as a majority of CPU power is controlled by nodes that are not cooperating to\nattack the network, they'll generate the longest chain and outpace attackers. The\nnetwork itself requires minimal structure. Messages are broadcast on a best effort\nbasis, and nodes can leave and rejoin the network at will, accepting the longest\nproof-of-work chain as proof of what happened while they were gone.\n1. Introduction\nCommerce on the Internet has come to rely almost exclusively on financial institutions serving as\ntrusted third parties to process electronic payments. While the system works well enough for\nmost transactions, it still suffers from the inherent weaknesses of the trust based model.\nCompletely non-reversible transactions are not really possible, since financial institutions cannot\navoid mediating disputes. The cost of mediation increases transaction costs, limiting the\nminimum practical transaction size and cutting off the possibility for small casual transactions,\nand there is a broader cost in the loss of ability to make non-reversible payments for non-\nreversible services. With the possibility of reversal, the need for trust spreads. Merchants must\nbe wary of their customers, hassling them for more information than they would otherwise need.\nA certain percentage of fraud is accepted as unavoidable. These costs and payment uncertainties\ncan be avoided in person by using physical currency, but no mechanism exists to make payments\nover a communications channel without a trusted party.\nWhat is needed is an electronic payment system based on cryptographic proof instead of trust,\nallowing any two willing parties to transact directly with each other without the need for a trusted\nthird party. Transactions that are computationally impractical to reverse would protect sellers\nfrom fraud, and routine escrow mechanisms could easily be implemented to protect buyers. In\nthis paper, we propose a solution to the double-spending problem using a peer-to-peer distributed\ntimestamp server to generate computational proof of the chronological order of transactions. The\nsystem is secure as long as honest nodes collectively control more CPU power than any\ncooperating group of attacker nodes.\n1\n2. Transactions\nWe define an electronic coin as a chain of digital signatures. Each owner transfers the coin to the\nnext by digitally signing a hash of the previous transaction and the public key of the next owner\nand adding these to the end of the coin. A payee can verify the signatures to verify the chain of\nownership.\nThe problem of course is the payee can't verify that one of the owners did not double-spend\nthe coin. A common solution is to introduce a trusted central authority, or mint, that checks every\ntransaction for double spending. After each transaction, the coin must be returned to the mint to\nissue a new coin, and only coins issued directly from the mint are trusted not to be double-spent.\nThe problem with this solution is that the fate of the entire money system depends on the\ncompany running the mint, with every transaction having to go through them, just like a bank.\nWe need a way for the payee to know that the previous owners did not sign any earlier\ntransactions. For our purposes, the earliest transaction is the one that counts, so we don't care\nabout later attempts to double-spend. The only way to confirm the absence of a transaction is to\nbe aware of all transactions. In the mint based model, the mint was aware of all transactions and\ndecided which arrived first. To accomplish this without a trusted party, transactions must be\npublicly announced [1], and we need a system for participants to agree on a single history of the\norder in which they were received. The payee needs proof that at the time of each transaction, the\nmajority of nodes agreed it was the first received.\n3. Timestamp Server\nThe solution we propose begins with a timestamp server. A timestamp server works by taking a\nhash of a block of items to be timestamped and widely publishing the hash, such as in a\nnewspaper or Usenet post [2-5]. The timestamp proves that the data must have existed at the\ntime, obviously, in order to get into the hash. Each timestamp includes the previous timestamp in\nits hash, forming a chain, with each additional timestamp reinforcing the ones before it.\n2\nBlock\nItem Item ...\nHash\nBlock\nItem Item ...\nHash\nTransaction\nOwner 1's\nPublic Key\nOwner 0's\nSignature\nHash\nTransaction\nOwner 2's\nPublic Key\nOwner 1's\nSignature\nHash\nVerify\nTransaction\nOwner 3's\nPublic Key\nOwner 2's\nSignature\nHash\nVerify\nOwner 2's\nPrivate Key\nOwner 1's\nPrivate Key\nSign\nSign\nOwner 3's\nPrivate Key\n4. Proof-of-Work\nTo implement a distributed timestamp server on a peer-to-peer basis, we will need to use a proof-\nof-work system similar to Adam Back's Hashcash [6], rather than newspaper or Usenet posts.\nThe proof-of-work involves scanning for a value that when hashed, such as with SHA-256, the\nhash begins with a number of zero bits. The average work required is exponential in the number\nof zero bits required and can be verified by executing a single hash.\nFor our timestamp network, we implement the proof-of-work by incrementing a","sample_text_capped":true,"shop":{"seller":"clink's shop — pay-per-call via x402 (USDC on Base), no account or API key","services":{"/x/search?query=":"$0.006 — live X/Twitter search, up to 20 newest tweets + engagement","/x/digest?query=":"$0.02 — same tweets + AI trend digest (sentiment, themes, driving accounts)","/x/user?username=":"$0.006 — latest tweets from one account, plus its pinned tweet","/x/profile?username=":"$0.005 — full profile: name, bio, followers, verified, join date","/x/tweet?id=":"$0.005 — one tweet by id, with live engagement","/x/replies?id=":"$0.006 — the reply thread under any post","/x/users?query=":"$0.006 — find X accounts by name, topic, or keyword","/pdf/text?url=":"$0.01 — convert any public PDF to plain text, full document in one call (no OCR)","/market/pulse?days=<1-60>":"$0.10 — agent-economy market report: revenue, payers, movers, launches, deaths, price bands from daily whole-market snapshots","/market/new?days=<1-60>&kind=":"$0.02 — every agent service launched in the window, with day-one traction","/market/service?id=":"$0.02 — one listing's day-by-day history (price, payers, calls, installs)","/vault/summary?entity=&level=":"$0.02 — lithium company/mine snapshot from primary regulator filings","/vault?entity=&level=":"$0.05 — full lithium dataset rows, every figure cited to a source filing","/vault/comparables?entity=&level=":"$0.20 — AISC cost-curve percentile + peer ranking across the tracked universe","/vault/spodumene-history?interval=&from=&to=":"$0.20 — full daily SC6 spodumene + lithium carbonate price series since May 2023 + producer realized prices, one call","/vault/sku/0.05?sku=&entity=&level=":"$0.05 — one field only: aisc, production, reserves, offtakes, ownership, royalties, spot, musk","/vault/sku/0.15?sku=&entity=&level=mine":"$0.15 — cost-curve percentile, or study NPV/IRR/capex","/vault/sku/0.25?sku=report&entity=&level=mine":"$0.25 — curated full report for one mine, every claim cited","/vault/sku/0.50?sku=rawdump&entity=&level=mine":"$0.50 — every extracted row for one mine","/find?q=":"free — search ~36,000 agent-callable tools (x402 + MCP) in one place"},"need_something_else":"POST /request with JSON {\"want\": \"the data or tool you need\", \"contact\": \"optional\"} — free. 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