Saylor Innovations Spaced Repet

Review dates, retention estimates and daily workload for spaced repetition

OtherUnknowneip155:8453Exactvia cdp

https://saylorinnovations.com/api/study/spaced-repetition

StudyProductivityPomodoroPertMeeting-cost

Settlements · 30d

1,649↑ 29%

No per-endpoint history for this service yet, so this is payments indexed to its PROVIDER's wallet over 30 days.

$15.76

Verified settled volume

1,657 settlements proven x402 by their on-chain EIP-3009 marker.

$0.010

Listed price

As published in the catalog. Always read the live 402 before paying.

1

Calls · 30d

Upstream's own call count for this endpoint, not ours.

1

Unique payers · 30d

Last called 2026-10-26 08:08Z

—

Upstream on-chain volume

Reported by the source catalog.

Paid to

0xA2A8dF0f7CaaBEa4e120a2568118f141569fc8aa

The wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.

Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913

Provider

The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.

Accepts

The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.

0.01USDC≈ $0.01 USD

on Base · exact scheme

Pay 0.01 USDC on Base to 0xA2A8…fc8aa. The signed payment is good for 2 minutes.

Paid to: 0xA2A8…fc8aa
USD Coin contract: 0x8335…02913
Payment window: 2 minutes
As published: 10000 smallest units

10000units

on Polygon · exact scheme

That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.

Paid to: 0xA2A8…fc8aa
Token contract: 0x3c49…c3359
Payment window: 2 minutes

10000units

on Arbitrum · exact scheme

That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.

Paid to: 0xA2A8…fc8aa
Token contract: 0xaf88…e5831
Payment window: 2 minutes

10000units

on solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp · exact scheme

That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.

Paid to: 7LSjfr…Xacy7
Token contract: EPjFWd…TDt1v
Payment window: 2 minutes

10000units

on solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp · exact scheme

That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.

Paid to: 7LSjfr…Xacy7
Token contract: Es9vMF…nwNYB
Payment window: 2 minutes

96690units

on solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp · exact scheme

That figure is in the token’s smallest units. Roundhouse does not hold this contract’s decimals, so it is shown as published rather than converted.

Paid to: 7LSjfr…Xacy7
Token contract: So1111…11112
Payment window: 2 minutes

The catalog’s raw entry

[
  {
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "extra": {
      "memo": "saylor:study:spaced-repetition",
      "name": "USD Coin",
      "note": "Base settles through an x402 facilitator. Send payload.signature and payload.authorization (EIP-3009); there is no self-submitted path on this network.",
      "version": "2",
      "facilitatorOnly": true,
      "assetTransferMethod": "eip3009"
    },
    "payTo": "0xA2A8dF0f7CaaBEa4e120a2568118f141569fc8aa",
    "amount": "10000",
    "scheme": "exact",
    "network": "eip155:8453",
    "maxTimeoutSeconds": 120
  },
  {
    "asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
    "extra": {
      "memo": "saylor:study:spaced-repetition",
      "name": "USD Coin",
      "note": "Polygon settles through an x402 facilitator. Send payload.signature and payload.authorization (EIP-3009); there is no self-submitted path on this network.",
      "version": "2",
      "facilitatorOnly": true,
      "assetTransferMethod": "eip3009"
    },
    "payTo": "0xA2A8dF0f7CaaBEa4e120a2568118f141569fc8aa",
    "amount": "10000",
    "scheme": "exact",
    "network": "eip155:137",
    "maxTimeoutSeconds": 120
  },
  {
    "asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
    "extra": {
      "memo": "saylor:study:spaced-repetition",
      "name": "USD Coin",
      "note": "Arbitrum settles through an x402 facilitator. Send payload.signature and payload.authorization (EIP-3009); there is no self-submitted path on this network.",
      "version": "2",
      "facilitatorOnly": true,
      "assetTransferMethod": "eip3009"
    },
    "payTo": "0xA2A8dF0f7CaaBEa4e120a2568118f141569fc8aa",
    "amount": "10000",
    "scheme": "exact",
    "network": "eip155:42161",
    "maxTimeoutSeconds": 120
  },
  {
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "extra": {
      "memo": "saylor:study:spaced-repetition",
      "session": "eyJhcnRpY2xlSWQiOiJzdHVkeTpzcGFjZWQtcmVwZXRpdGlvbiIsInJlZmVyZW5jZSI6IjRxWEpkSjFIVDdGbXhXVVRuRDJSaFBSdVo2U3F5SFBnVjI1R2Z6amtlUE5BIiwicmVjaXBpZW50IjoiN0xTamZySmY4Zk5zQjhWQTl1N04zV0VuMjVzbVFMcG9iM1N2eVV2WGFjeTciLCJtaW50IjoiRVBqRldkZDVBdWZxU1NxZU0ycU4xeHp5YmFwQzhHNHdFR0drWnd5VER0MXYiLCJtaW5BbW91bnQiOjEwMDAwLCJleHAiOjE3OTMwMDIyMjEzNzh9.Cw375YHSYSMYNx1T46HMjtHr4pzDdfgiW2nOiTOQKxo",
      "feePayer": "Hc3sdEAsCGQcpgfivywog9uwtk8gUBUZgsxdME1EJy88",
      "reference": "4qXJdJ1HT7FmxWUTnD2RhPRuZ6SqyHPgV25GfzjkePNA"
    },
    "payTo": "7LSjfrJf8fNsB8VA9u7N3WEn25smQLpob3SvyUvXacy7",
    "amount": "10000",
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "maxTimeoutSeconds": 120
  },
  {
    "asset": "Es9vMFrzaCERmJfrF4H2FYD4KCoNkY11McCe8BenwNYB",
    "extra": {
      "memo": "saylor:study:spaced-repetition",
      "session": "eyJhcnRpY2xlSWQiOiJzdHVkeTpzcGFjZWQtcmVwZXRpdGlvbiIsInJlZmVyZW5jZSI6IjViakJWUUh0YjlmN1Fzb2ZmaDd3d1dIbktDVTRCR0dEUHM5dzZrQmVSOG5lIiwicmVjaXBpZW50IjoiN0xTamZySmY4Zk5zQjhWQTl1N04zV0VuMjVzbVFMcG9iM1N2eVV2WGFjeTciLCJtaW50IjoiRXM5dk1GcnphQ0VSbUpmckY0SDJGWUQ0S0NvTmtZMTFNY0NlOEJlbndOWUIiLCJtaW5BbW91bnQiOjEwMDAwLCJleHAiOjE3OTMwMDIyMjEzNzh9.sx9WR4zN5FzDZXS2cg0zeGL5US-YRpyEozfg8bcytt4",
      "feePayer": "Hc3sdEAsCGQcpgfivywog9uwtk8gUBUZgsxdME1EJy88",
      "reference": "5bjBVQHtb9f7Qsoffh7wwWHnKCU4BGGDPs9w6kBeR8ne"
    },
    "payTo": "7LSjfrJf8fNsB8VA9u7N3WEn25smQLpob3SvyUvXacy7",
    "amount": "10000",
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "maxTimeoutSeconds": 120
  },
  {
    "asset": "So11111111111111111111111111111111111111112",
    "extra": {
      "memo": "saylor:study:spaced-repetition",
      "note": "Native SOL: send lamports with a system transfer, not an SPL transfer. Price is quoted live and this quote expires in 120s.",
      "native": true,
      "session": "eyJhcnRpY2xlSWQiOiJzdHVkeTpzcGFjZWQtcmVwZXRpdGlvbiIsInJlZmVyZW5jZSI6IkI0dXZUakdiNW5tU0NXTE13UWVlcVBOalpSeGlyRDRKaEc3aWd1bmk4UnlKIiwicmVjaXBpZW50IjoiN0xTamZySmY4Zk5zQjhWQTl1N04zV0VuMjVzbVFMcG9iM1N2eVV2WGFjeTciLCJtaW50IjpudWxsLCJtaW5BbW91bnQiOjk2NjkwLCJleHAiOjE3OTMwMDIyMjEzNzh9.xDqlyFp3dz2MFUCSKSTOtj-mlsk2l9pSC03Ow_sRIf0",
      "reference": "B4uvTjGb5nmSCWLMwQeeqPNjZRxirD4JhG7iguni8RyJ",
      "solUsdPrice": 100.32,
      "quotedLamports": "99681"
    },
    "payTo": "7LSjfrJf8fNsB8VA9u7N3WEn25smQLpob3SvyUvXacy7",
    "amount": "96690",
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "maxTimeoutSeconds": 120
  }
]

Extensions

{
  "bazaar": {
    "info": {
      "input": {
        "type": "http",
        "method": "GET",
        "queryParams": {
          "grades": "4,4,3,5,4,4",
          "method": "sm2",
          "start_date": "2026-11-01",
          "retention_target": "90",
          "new_cards_per_day": "20",
          "seconds_per_review": "8"
        }
      },
      "output": {
        "type": "json",
        "example": {
          "first_reviews_days": [
            1,
            6
          ]
        }
      }
    },
    "schema": {
      "type": "object",
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "required": [
        "input"
      ],
      "properties": {
        "input": {
          "type": "object",
          "required": [
            "type",
            "method"
          ],
          "properties": {
            "type": {
              "type": "string",
              "const": "http"
            },
            "method": {
              "enum": [
                "GET"
              ],
              "type": "string"
            },
            "queryParams": {
              "type": "object",
              "required": [
                "start_date"
              ],
              "properties": {
                "grades": {
                  "type": "string",
                  "description": "optional SM-2 recall grades 0-5 for each review separated by commas, default all 4 (query)"
                },
                "method": {
                  "type": "string",
                  "description": "optional sm2 (default), leitner or expanding (query)"
                },
                "start_date": {
                  "type": "string",
                  "description": "required first study date YYYY-MM-DD (query)"
                },
                "retention_target": {
                  "type": "string",
                  "description": "optional target retention percent, default 90 (query)"
                },
                "new_cards_per_day": {
                  "type": "string",
                  "description": "optional new cards added per day for the workload estimate (query)"
                },
                "seconds_per_review": {
                  "type": "string",
                  "description": "optional average seconds per card review, default 8 (query)"
                }
              }
            }
          },
          "additionalProperties": false
        },
        "output": {
          "type": "object",
          "required": [
            "type"
          ],
          "properties": {
            "type": {
              "type": "string",
              "const": "json"
            },
            "example": {
              "type": "object"
            }
          }
        }
      }
    }
  }
}

Provenance

Seen in the source catalog: 2026-10-26 08:08Z
Last indexed by Roundhouse: 2026-10-26 15:20Z
Last enriched (probe, favicon, geo): —
x402 version: 2
Max timeout: 120s
Liveness probe: Not probed

Hand this page to an agent

Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.

GET api.roundhouseai.io/v0/endpoints

No per-endpoint history for this service yet, so this is payments indexed to its PROVIDER's wallet over 30 days. Verified volume counts only settlements with an on-chain EIP-3009 marker.

Show the prompt

Using Roundhouse, look up the x402 service Saylor Innovations  Spaced Repet and tell me whether it is
worth paying: what a call costs, whether the endpoint answered when last probed, and what
its payment record actually shows.

curl -s 'https://api.roundhouseai.io/v0/endpoints?q=Saylor%20Innovations%20%20Spaced%20Repet'
curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>'

Then call it: read the price from the live 402 at https://saylorinnovations.com/api/study/spaced-repetition, never from
a cached figure, and pay with an x402 client.

The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except
/v0/unified* and /v0/endpoints. Either pay over x402 (mint a personal key for $0.01 at
GET https://api.roundhouseai.io/v0/test/x402), or ask me for an organization key, which I create at
https://roundhouseai.io/dashboard/connections. If you have neither, ask before going further.

If you do not have Roundhouse tools or skills installed, read
https://roundhouseai.io/skill.md first — it is the whole procedure.