Execute a prompt

Call any prompt by name over HTTPS. Base URL:

https://router.promptlab.vernalabs.net

All routes are versioned under /v1 and scoped to a project: /v1/:projectId/.... Authenticate with the x-api-key header — see Authentication.

Endpoints

Method	Path	Purpose
`POST`	`/v1/:projectId/prompts/:promptName/execute`	Execute a stored prompt
`GET`	`/v1/:projectId/prompts`	List active prompts
`GET`	`/v1/:projectId/prompts/:promptName`	Get one prompt’s contract
`GET`	`/v1/:projectId/jobs/:jobId`	Poll an async job

Execute

curl -X POST \
  https://router.promptlab.vernalabs.net/v1/YOUR_PROJECT_ID/prompts/summarize-ticket/execute \
  -H "x-api-key: plp_xxx_xxx" \
  -H "Content-Type: application/json" \
  -d '{
        "inputs": { "ticket": "User cannot log in after a password reset." },
        "options": { "temperature": 0.2 }
      }'

Request body

Field	Type	Notes
`inputs`	object	Values for the prompt’s `{{variables}}`
`version`	string	Pin a prompt version (defaults to the active one)
`options`	object	Per-call overrides: `temperature`, `maxTokens`, `seed`, `reasoningEffort`, `executionMode` (`"sync"` \| `"async"`), …
`context`	object	`{ agentId?, metadata? }`
`trace`	object	`{ correlationId? }`

The endpoint returns 200 with a response envelope.

Sending files (multipart)

For prompts that take images or other files, send multipart/form-data: one or more files parts (up to 20) plus a JSON payload field (or individual inputs / options / context / trace JSON string fields).

Async jobs

Media generation runs asynchronously. When the response status is queued or running, poll the job until it finishes:

curl https://router.promptlab.vernalabs.net/v1/YOUR_PROJECT_ID/jobs/JOB_ID \
  -H "x-api-key: plp_xxx_xxx"

You can force sync or async with options.executionMode. Text defaults to sync; media defaults to async.

List and inspect prompts

# list active prompts
curl https://router.promptlab.vernalabs.net/v1/YOUR_PROJECT_ID/prompts \
  -H "x-api-key: plp_xxx_xxx"

# get one prompt's contract (add ?version=3&includeTemplate=true)
curl https://router.promptlab.vernalabs.net/v1/YOUR_PROJECT_ID/prompts/summarize-ticket \
  -H "x-api-key: plp_xxx_xxx"

Response envelope — the shape you get back.
Embeddings — create vector embeddings.