---
title: "Get Llm Ttfb"
method: GET
path: "/developer/llm-ttfb"
tags: ["Developer", "Developer - LLM TTFB"]
---

# Get Llm Ttfb

`GET /developer/llm-ttfb`

Get combined LLM TTFB data: synthetic Bedrock benchmarks and real-world Vapi call latency.
Restricted to developer users in dev environment only.

## Query parameters

- `time_range` '24h' | '7d' | '30d'

## Response `200`

Successful Response

- LLMTTFBResponse — Combined response with Bedrock TTFB and Vapi LLM latency measurements
  - `bedrock_measurements` BedrockTTFBMeasurementSchema[] — Bedrock TTFB measurement data points
    - `id` string, uuid, required — Measurement ID
    - `model` string, required — Bedrock model ID
    - `region` string, required — AWS region
    - `ttfb_ms` number, nullable — Time to first byte in milliseconds
    - `total_time_ms` number, nullable — Total response time in milliseconds
    - `response_length` integer, nullable — Response text length
    - `error` string, nullable — Error message if measurement failed
    - `created_at` string, required — Measurement timestamp
  - `vapi_measurements` VapiLLMLatencyMeasurementSchema[] — Vapi LLM latency measurement data points
    - `id` string, uuid, required — Measurement ID
    - `vapi_call_id` string, required — Vapi call ID
    - `model` string, nullable — LLM model used (e.g. claude-sonnet-4-6)
    - `model_latency_avg_ms` number, nullable — Average model latency in milliseconds
    - `turn_count` integer, nullable — Number of turns with latency data
    - `turn_latencies_ms` unknown[], nullable — Raw turn latencies array
      - unknown
    - `call_duration_seconds` integer, nullable — Call duration in seconds
    - `call_ended_at` string, nullable — When the call ended (ISO timestamp)
    - `created_at` string, required — Row insertion timestamp

## Other responses

- `422` — Validation Error

---

[API](https://skmtc.dev/openintake/apis/fastapi.md) · [All operations](https://skmtc.dev/openintake/apis/fastapi/llms.txt) · [OpenAPI document](https://skmtc-service-production.skmtc.workers.dev/v1/apis/openintake/fastapi/revisions/4a81645b59f6/schema)