Gemini 3.8 Flash TTS Serverless API
Direct expressive text-to-speech with two-speaker dialogue, 130+ languages.
POST /v2/gemini-3.8-flash-tts · submit + poll 1# pip install "segmind>=1.1.0"
2# export SEGMIND_API_KEY="YOUR_API_KEY"
3import segmind
4
5# Async (v2): submit to the queue and block until COMPLETED.
6# run() returns the final result dict (600s deadline, 1.0s poll by default).
7result = segmind.run(
8 "gemini-3.8-flash-tts",
9 text="It's fifteen seconds from the final whistle, and it's still Rovers one, City one. <short pause> Mateo Rinaldi picks it up on the halfway line... he's past one man, past two — can he finish it from here? <gasp> He shoots... and it's IN! Rinaldi wins it at the death, and the whole Olimpico is on its feet!",
10 voice_1="Fenrir",
11 style="live stadium football commentator, tense and hushed at first, then erupting into euphoric excitement on the goal",
12 temperature=1.1,
13)
14print(result["status"]) # COMPLETED
15print(result.get("output")) # model output (e.g. media URL)
16print(result["metrics"]["inference_time"]) # server compute seconds
17
18# --- Or submit + poll manually (track request_id, control the cadence) ---
19from segmind import SegmindClient, InferenceFailed, InferenceTimeout
20
21client = SegmindClient() # reads SEGMIND_API_KEY
22payload = {
23 "text": "It's fifteen seconds from the final whistle, and it's still Rovers one, City one. <short pause> Mateo Rinaldi picks it up on the halfway line... he's past one man, past two — can he finish it from here? <gasp> He shoots... and it's IN! Rinaldi wins it at the death, and the whole Olimpico is on its feet!",
24 "voice_1": "Fenrir",
25 "style": "live stadium football commentator, tense and hushed at first, then erupting into euphoric excitement on the goal",
26 "temperature": 1.1,
27}
28job = client.submit_async("gemini-3.8-flash-tts", **payload)
29print(job.request_id) # available immediately
30try:
31 result = job.wait(timeout=600, interval=1.0)
32except InferenceTimeout as e:
33 print("still running:", e.request_id)
34except InferenceFailed as e:
35 print("failed:", e.detail) 1# pip install "segmind>=1.1.0"
2# export SEGMIND_API_KEY="YOUR_API_KEY"
3import segmind
4
5# Async (v2): submit to the queue and block until COMPLETED.
6# run() returns the final result dict (600s deadline, 1.0s poll by default).
7result = segmind.run(
8 "gemini-3.8-flash-tts",
9 text="It's fifteen seconds from the final whistle, and it's still Rovers one, City one. <short pause> Mateo Rinaldi picks it up on the halfway line... he's past one man, past two — can he finish it from here? <gasp> He shoots... and it's IN! Rinaldi wins it at the death, and the whole Olimpico is on its feet!",
10 voice_1="Fenrir",
11 style="live stadium football commentator, tense and hushed at first, then erupting into euphoric excitement on the goal",
12 temperature=1.1,
13)
14print(result["status"]) # COMPLETED
15print(result.get("output")) # model output (e.g. media URL)
16print(result["metrics"]["inference_time"]) # server compute seconds
17
18# --- Or submit + poll manually (track request_id, control the cadence) ---
19from segmind import SegmindClient, InferenceFailed, InferenceTimeout
20
21client = SegmindClient() # reads SEGMIND_API_KEY
22payload = {
23 "text": "It's fifteen seconds from the final whistle, and it's still Rovers one, City one. <short pause> Mateo Rinaldi picks it up on the halfway line... he's past one man, past two — can he finish it from here? <gasp> He shoots... and it's IN! Rinaldi wins it at the death, and the whole Olimpico is on its feet!",
24 "voice_1": "Fenrir",
25 "style": "live stadium football commentator, tense and hushed at first, then erupting into euphoric excitement on the goal",
26 "temperature": 1.1,
27}
28job = client.submit_async("gemini-3.8-flash-tts", **payload)
29print(job.request_id) # available immediately
30try:
31 result = job.wait(timeout=600, interval=1.0)
32except InferenceTimeout as e:
33 print("still running:", e.request_id)
34except InferenceFailed as e:
35 print("failed:", e.detail)API Endpoint
https://api.segmind.com/v1/gemini-3.8-flash-ttsParameters
textrequiredstringTranscript to speak, read verbatim; required. Add inline cues like <laughs>, <sigh> or <short pause>. For two speakers, start each turn with its voice name, e.g. 'Kore: Hi!' then 'Puck: Hello!'.
"It's fifteen seconds from the final whistle, and it's still Rovers one, City one. <short pause> Mateo Rinaldi picks it up on the halfway line... he's past one man, past two — can he finish it from here? <gasp> He shoots... and it's IN! Rinaldi wins it at the death, and the whole Olimpico is on its feet!"styleoptionalstringPlain-English delivery direction applied to every line. Use for emotion, pacing or accent, e.g. 'whispered urgently' or 'cheerful, upbeat'.
temperatureoptionalnumberExpressiveness from 0 to 2. Use 0.2-0.5 for steady narration, 0.8-1.4 for emotional, animated delivery.
0.4Range: 0 - 2voice_1optionalstringPrimary speaker, one of 30 studio voices. Pick the timbre that fits your character; it also leads two-speaker scenes.
"Kore""Kore""Puck""Charon""Zephyr""Fenrir""Leda""Orus""Aoede""Callirrhoe""Autonoe"+20 morevoice_2optionalstringOptional second speaker for two-person dialogue (max two). Choose a different voice and start each of that speaker's lines with this voice name.
"Kore""Puck""Charon""Zephyr""Fenrir""Leda""Orus""Aoede""Callirrhoe""Autonoe"+20 moreResponse Type
Returns: Audio
Asynchronous requests (v2)
Use Async for video, long-running (>~60s), or high-concurrency workloads; Sync is simplest for fast image & LLM calls. Async submits a request and you poll it to completion.
- 1
POST /v2/gemini-3.8-flash-ttsSubmit — returns request_id, status_url, response_url
- 2
GET /v2/requests/{id}/statusPoll — until COMPLETED or FAILED
- 3
GET /v2/requests/{id}Result — final response body
Status states
- A FAILED request is served as HTTP 422 — the body still carries the error detail.
- An unknown or expired request_id returns HTTP 404.
- Results are retained for 1 hour, then expire.
- Content / RAI blocks surface as FAILED, not a separate state.
- Track completion by polling the status endpoint.
Common Error Codes
The API returns standard HTTP status codes. Detailed error messages are provided in the response body.
Bad Request
Invalid parameters or request format
Unauthorized
Missing or invalid API key
Forbidden
Insufficient permissions
Not Found
Model or endpoint not found
Insufficient Credits
Not enough credits to process request
Rate Limited
Too many requests
Server Error
Internal server error
Bad Gateway
Service temporarily unavailable
Timeout
Request timed out