API Reference

Manage reusable templates and versioned template changes

This page is the source of truth for the template lifecycle: list, create, update, delete, inspect version history, and roll back to a prior snapshot for deterministic render output.

The machine readable contract for these customer account routes lives in /docs/account. This docs page stays more explanatory so template workflow, versioning rules, and render handoff remain easy to follow in one place.

Auth model

All template lifecycle routes

Authorization: Bearer ACCESS_TOKEN

Templates are account resources. Every route on this page requires signed in user bearer auth.

Render usage after create

templateId and optional templateVersionId

Use the returned template identifier on rendering routes. Use templateVersionId only when you need deterministic historical output.

Version history access

Professional and Business plans

Version history and rollback are plan-gated. Accounts without versioning access receive409 Conflict. Eligible plans retain the newest 25 versions per template.

Credential

All routes on this page use bearer auth because templates are account resources.

Render handoff

Use templateId in render requests, and add templateVersionId only when you need one historical snapshot.

Versioning rule

Version history and rollback are gated by plan and return conflict responses when versioning is unavailable.

Retention cap

Version history keeps the 25 most recent snapshots for each template on version-enabled plans.

Open single render reference Open account OpenAPI Follow the render-from-template guide

List templates

List saved templates for the authenticated account

Use this route to inventory template IDs, names, and current snapshots. Results are returned newest first by createdAt.

GET/user/templates

200 OK401 Unauthorized

Request

Authorization

required bearer token

Lists templates for the signed in account only.

Response

templates

array<object>

Template records ordered newest first by create time.

templates[].id

UUID

Stable template identifier used in render requests.

templates[].name

string

Human-readable template name unique within the account.

templates[].content

string

Current HTML content saved for the template.

templates[].sampleData

string

Saved sample JSON string, if present.

templates[].createdAt

ISO 8601 datetime

Timestamp when the template was created.

templates[].updatedAt

ISO 8601 datetime

Timestamp of the latest mutation on the template.

Create template

Create a reusable template record

Create fails with 409 Conflict when the name already exists or the account template limit is reached.

POST/user/templates

200 OK400 Bad Request401 Unauthorized409 Conflict

Request

name

required string, max 100

Template display name, unique per account.

content

required string, max 200,000

HTML content used for render-time substitution. Must contain meaningful body content and safe template placeholders.

sampleData

optional JSON-object string, max 50,000

Serialized JSON object used by preview or test workflows.

Response

UUID

Template identifier to store for future renders.

name

string

Unique template name that was persisted for the account.

content

string

Saved HTML snapshot used by future render calls.

sampleData

string

Stored JSON string (or empty string when omitted).

createdAt

ISO 8601 datetime

Timestamp when the template record was first created.

updatedAt

ISO 8601 datetime

Timestamp of the latest template mutation.

Update template

Update name, content, or sample data for one template

Updating content may create a version snapshot on plans that include version history.

PATCH/user/templates/:id

200 OK400 Bad Request401 Unauthorized404 Not Found409 Conflict

Request

required path UUID

Template identifier owned by the signed in account.

name

optional string, max 100

Must remain unique when changed.

content

optional string, max 200,000

Updates the active HTML content snapshot and must still pass template placeholder safety checks.

sampleData

optional JSON-object string, max 50,000

Replaces the stored sample JSON string.

Response

UUID

Stable template identifier returned for follow up updates and renders.

name

string

Current unique template name after update processing.

content

string

Current active HTML snapshot for rendering.

sampleData

string

Current stored sample JSON string.

createdAt

ISO 8601 datetime

Original creation timestamp, unchanged by update.

updatedAt

ISO 8601 datetime

Mutation timestamp after the update is saved.

Delete template

Delete one template by identifier

Delete is permanent for the current template record and returns a success confirmation.

DELETE/user/templates/:id

200 OK401 Unauthorized404 Not Found

Request

required path UUID

Identifier for the account template to remove.

Response

success

boolean

Returns true when deletion succeeds.

Version history

List saved versions for a single template

Version history supports audits, deterministic rerenders, and rollback preparation.

GET/user/templates/:id/versions

200 OK401 Unauthorized404 Not Found409 Conflict

Request

required path UUID

Template identifier whose versions should be listed.

Response

versions

array<object>

Version snapshots ordered by versionNumber descending.

versions[].id

UUID

Version identifier used by rollback.

versions[].versionNumber

integer

Monotonic version counter for that template.

versions[].name

string

Template name captured at that historical snapshot.

versions[].content

string

HTML content captured for that version.

versions[].sampleData

string

Serialized sample JSON captured for that version.

versions[].createdAt

ISO 8601 datetime

Timestamp when this version snapshot was written.

Rollback

Restore a previous version as the current template

Rollback applies one historical snapshot, saves it as the current template, and returns the updated template state.

POST/user/templates/:id/versions/:versionId/rollback

200 OK401 Unauthorized404 Not Found409 Conflict

Request

required path UUID

Template identifier to modify.

versionId

required path UUID

Historical version snapshot to restore.

Response

UUID

Template identifier that was rolled back.

name

string

Name restored from the selected historical version.

content

string

Content restored from the selected historical version.

sampleData

string

Sample JSON restored from the selected historical version.

createdAt

ISO 8601 datetime

Original creation timestamp for the template record.

updatedAt

ISO 8601 datetime

Timestamp of the rollback mutation.

Next steps

Use template IDs in render flows

Need the render contract?

Open single render reference

Use the single render page for templateId, templateVersionId, data, and accepted-work behavior.

Reference

Need real examples?

Open render-from-template guide

Use the guide for template data examples, saved-template workflow, and version-pinned render requests.

Guide

Template lifecycle overview

GET

curl "https://api.solidrelay.io/user/templates" \
  -H "Authorization: Bearer ACCESS_TOKEN"

200 OK

{
  "templates": [
    {
      "id": "2a2bc604-feb7-41b5-8e2c-2e2784ecb67d",
      "name": "Invoice template",
      "content": "<html><body><h1>Invoice #{{invoiceNumber}}</h1></body></html>",
      "sampleData": "{\"invoiceNumber\":\"1024\"}",
      "createdAt": "2026-04-01T10:30:00.000Z",
      "updatedAt": "2026-04-03T14:11:22.000Z"
    }
  ]
}

GET /user/templates

GET

curl "https://api.solidrelay.io/user/templates" \
  -H "Authorization: Bearer ACCESS_TOKEN"

200 OK

{
  "templates": [
    {
      "id": "2a2bc604-feb7-41b5-8e2c-2e2784ecb67d",
      "name": "Invoice template",
      "content": "<html><body><h1>Invoice #{{invoiceNumber}}</h1></body></html>",
      "sampleData": "{\"invoiceNumber\":\"1024\"}",
      "createdAt": "2026-04-01T10:30:00.000Z",
      "updatedAt": "2026-04-03T14:11:22.000Z"
    }
  ]
}

POST /user/templates

POST

curl -X POST "https://api.solidrelay.io/user/templates" \
  -H "Authorization: Bearer ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Invoice template",
    "content": "<html><body><h1>Invoice #{{invoiceNumber}}</h1></body></html>",
    "sampleData": "{"invoiceNumber":"1024"}"
  }'

200 OK

{
  "id": "2a2bc604-feb7-41b5-8e2c-2e2784ecb67d",
  "name": "Invoice template",
  "content": "<html><body><h1>Invoice #{{invoiceNumber}}</h1></body></html>",
  "sampleData": "{\"invoiceNumber\":\"1024\"}",
  "createdAt": "2026-04-01T10:30:00.000Z",
  "updatedAt": "2026-04-01T10:30:00.000Z"
}

PATCH /user/templates/:id

PATCH

curl -X PATCH "https://api.solidrelay.io/user/templates/2a2bc604-feb7-41b5-8e2c-2e2784ecb67d" \
  -H "Authorization: Bearer ACCESS_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "Invoice template v2",
    "content": "<html><body><h1>Invoice #{{invoiceNumber}}</h1><p>{{customerName}}</p></body></html>"
  }'

200 OK

{
  "id": "2a2bc604-feb7-41b5-8e2c-2e2784ecb67d",
  "name": "Invoice template",
  "content": "<html><body><h1>Invoice #{{invoiceNumber}}</h1></body></html>",
  "sampleData": "{\"invoiceNumber\":\"1024\"}",
  "createdAt": "2026-04-01T10:30:00.000Z",
  "updatedAt": "2026-04-01T10:30:00.000Z"
}

DELETE /user/templates/:id

DELETE

curl -X DELETE "https://api.solidrelay.io/user/templates/2a2bc604-feb7-41b5-8e2c-2e2784ecb67d" \
  -H "Authorization: Bearer ACCESS_TOKEN"

200 OK

{
  "success": true
}

GET /user/templates/:id/versions

GET

curl "https://api.solidrelay.io/user/templates/2a2bc604-feb7-41b5-8e2c-2e2784ecb67d/versions" \
  -H "Authorization: Bearer ACCESS_TOKEN"

200 OK

{
  "versions": [
    {
      "id": "ab8e7dbd-14d6-412e-a36d-d3f644ae8a76",
      "versionNumber": 7,
      "name": "Invoice template v2",
      "content": "<html><body><h1>Invoice #{{invoiceNumber}}</h1><p>{{customerName}}</p></body></html>",
      "sampleData": "{\"invoiceNumber\":\"1024\",\"customerName\":\"Luna Inc\"}",
      "createdAt": "2026-04-03T14:11:22.000Z"
    }
  ]
}

POST /user/templates/:id/versions/:versionId/rollback

POST

curl -X POST "https://api.solidrelay.io/user/templates/2a2bc604-feb7-41b5-8e2c-2e2784ecb67d/versions/ab8e7dbd-14d6-412e-a36d-d3f644ae8a76/rollback" \
  -H "Authorization: Bearer ACCESS_TOKEN"

200 OK

{
  "id": "2a2bc604-feb7-41b5-8e2c-2e2784ecb67d",
  "name": "Invoice template",
  "content": "<html><body><h1>Invoice #{{invoiceNumber}}</h1></body></html>",
  "sampleData": "{\"invoiceNumber\":\"1024\"}",
  "createdAt": "2026-04-01T10:30:00.000Z",
  "updatedAt": "2026-04-01T10:30:00.000Z"
}