> For the complete documentation index, see [llms.txt](https://docs.emudhradigital.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.emudhradigital.com/api-reference/esign-v3-api-ca-ekyc-account/esign-v3-api-overview.md).

# eSign v3 API Overview

The eSign v3 API implements **CCA eSign API 3.3 (CA eKYC Account based)**. Signers authenticate to their eMudhra eKYC account with a PIN plus a second factor. The API is **asynchronous**.

{% hint style="info" %}
**Interactive reference (Swagger / OpenAPI):** [eSign v3 API — Swagger](https://todo-swagger-url/esign-v3)

*Placeholder link — to be replaced with the published Swagger URL.*
{% endhint %}

## Operations

| # | Operation        | Method                                | Payload                 | Response                           |
| - | ---------------- | ------------------------------------- | ----------------------- | ---------------------------------- |
| 1 | Initiate signing | HTTPS POST `application/xml`          | Signed `<Esign>`        | `<EsignResp status="2">` (pending) |
| 2 | Signer redirect  | Browser POST to eMudhra               | `txnref` = Base64(\`txn | resCode\`)                         |
| 3 | Final result     | eMudhra → HTTPS POST to `responseUrl` | Signed `<EsignResp>`    | —                                  |
| 4 | Status check     | HTTPS POST `application/xml`          | Signed `<EsignStatus>`  | `<EsignResp>`                      |

## Key limits

| Item                  | Value                 |
| --------------------- | --------------------- |
| Documents per request | Up to 5               |
| `maxWaitPeriod`       | Minutes; default 1440 |
| `signingAlgorithm`    | `RSA` or `ECDSA`      |
| Status retention      | ≥ 30 days             |