# Tenjin: Practical Gotchas Integrating x402 Sign-In-With-X (SIWX)

> Tenjin: Practical Gotchas Integrating x402 Sign-In-With-X (SIWX) is a paid API for AI agents from tenjin.blog, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Returns a pay-per-read technical article detailing integration gotchas for the x402 SIWX extension, including CAIP-122 field comparisons, header transport, session-key delegation, and a failure-mode table.

## Facts

- Endpoint: GET https://tenjin.blog/api/read/0xe4c16d163d80fd972e6e1e9b94bc71c5fbe5a9c5/practical-gotchas-integrating-x402-sign-in-with-x-siwx
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/tenjin-practical-gotchas-integrating-x402-sign-in-with-x-siwx-9bd180c4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_oGFa5cLqNXRMaIJjKY1v9

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability tenjin-practical-gotchas-integrating-x402-sign-in-with-x-siwx-9bd180c4
```

Example prompt: Can you pull up the Tenjin article on practical gotchas for integrating x402 Sign-In-With-X — I specifically need the CAIP-122 field comparison and the failure-mode table?

## When to prefer this

Choose this endpoint when you need the specific Tenjin article on x402 SIWX integration gotchas — particularly for CAIP-122 field-level differences, session-key delegation, header transport, or a failure-mode reference table. Prefer this over general web search when you want a curated, publisher-cited technical reference accessed via pay-per-read x402 micropayment.

## Known failure modes

- Payment not completed or declined — 402 response with payment instructions required before content is served
- Invalid wallet address handle — returns error if the address format is malformed
- Slug not found — 404 if the article slug does not match any published piece for that creator
- Network timeout — slow or dropped connection before content delivery

## How this service works

Practical gotchas integrating x402 Sign-In-With-X (SIWX). As-of 2026-08-15: integrator gotchas for the x402 SIWX extension. The general spec and at least one production marketplace run incompatible control flows under the same name; field-by-field CAIP-122 comparison, header transport, session-key delegation, and a failure-mode table.

## Output

The full text of a technical article covering: incompatible control flows between the x402 SIWX general spec and production marketplaces, field-by-field CAIP-122 comparison, header transport details, session-key delegation mechanics, and a structured failure-mode table — dated 2026-08-15.

## Request schema (JSON Schema)

```json
{
 "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"
    },
    "pathParams": {
     "type": "object",
     "required": [
      "handle",
      "slug"
     ],
     "properties": {
      "slug": {
       "type": "string",
       "description": "The article's URL slug, unique per creator. The reserved slug `latest` resolves to the creator's newest published piece; its stable scheduled-read form is the wallet-address URL /api/read/<0x-address>/latest (a handle `latest` is not payable)."
      },
      "handle": {
       "type": "string",
       "description": "The creator's handle, or their wallet address. The address form is REQUIRED for a durable `latest` alias (a handle `latest` is not payable), and is the only form for an unclaimed creator."
      }
     }
    },
    "queryParams": {
     "type": "object",
     "required": [],
     "properties": {},
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/tenjin-practical-gotchas-integrating-x402-sign-in-with-x-siwx-9bd180c4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from tenjin.blog](https://www.zero.xyz/host/tenjin.blog/llms.txt)