Developers
Building on the Sume API: keys and hosts, jobs and runs, polling, webhooks, idempotency, errors and rate limits, the SDK, the CLI, and MCP auth.
Avatar video quality settings: standard, plus or max?
Sume's talking avatar video takes quality standard, plus (default) or max. What each means, the other output fields, and how the preview relates to final tier.
AI avatar video length limit: 4 to 60 seconds per job
Sume's avatar video accepts an estimated 4 to 60 seconds per job, for scripts, scenes, previews and inline captions. Where it applies and what to do outside it.
Talking photo AI without watermark: what Sume documents
Sume's docs describe no watermark option for talking photo clips. They do fix the inputs: a still, Sume-hosted audio under 10 MB, 1-300 s or 5-14.8 s by route.
Team API keys: which wallet does a Sume run charge?
A Sume run charges the workspace its API key belongs to. A team key spends the team wallet; a personal key on a team Format is refused with 403.
TikTok trending videos: yesterday vs this month window
Sume's trending video search takes six windows, from yesterday to all-time. Which to pick for a spike versus a steady trend, and what each default is.
TikTok trending videos by country: Korea, US and UK via API
Pass a two-letter region such as KR, US or GB to Sume's trending video search to scope results to one country. Browse across US, GB and KR is not in production.
Timeline error too_many_chained_transitions: how to fix it
Timeline 1.0 refuses more than 8 adjacent fades with too_many_chained_transitions. Insert a hard cut. Also transition_too_long, transition_not_frame_aligned.
Render a vertical 1080x1920 video from clips with an API
Timeline 1.0 defaults to a 1080x1920 MP4. Set output width, height and fps, and pick fit cover, contain, stretch or blur for clips that do not match the frame.
Text to speech long text limit: 1,200 seconds, not just characters
Sume TTS 1.0 has two limits: 20,000 characters in, 1,200 seconds of audio out. Over the audio limit it fails with tts_duration_exceeded and captures no credit.
Text to speech sentence timestamps API: one lip-sync clip each
Sume TTS 1.0 returns gapless sentence segments; with wav output each gets its own audio_url, ready to drive a lip-sync clip. Request shape and the 5 s catch.
TTS WAV or MP3 for video: keep WAV until the last mux
Sume TTS 1.0 defaults to mp3 at 44100 Hz and 128 kbps. If the audio will be joined, sliced or muxed into video, ask for wav; mp3 adds padding at every edge.
Veo 3.1 personGeneration: allow_adult vs allow_all by mode
Veo 3.1 personGeneration is allow_all for text-to-video, allow_adult for image modes, and allow_adult only in some regions. Sume has no such field.
verifyWebhook async: forget await and you get a promise
verifyWebhook in @sume-com/sdk is async. Without await, a Promise is truthy, so your signature check never rejects. The await, raw body and replay rules.
unsupported_media_source: why the media API rejects your video URL
unsupported_media_source means video_url is not on the Sume media host. Import the clip first; which Sume video endpoints need a hosted URL and which don't.
video_trim_range_conflict: send end or duration, not both
The video trim API returns video_trim_range_conflict when a body has both end and duration. Send start plus exactly one of them; other range errors explained.
Wan 3.0 prompt guide for API users: prompt vs request fields
Write a Wan 3.0 prompt as a shot list with sound cues, and set length and size in request fields. What to put in the prompt and what to send to Sume's wan-3.0.
Wan 3.0 seed and size: why the API returns 400 unsupported_parameter
wan-3.0 on Sume rejects seed and size rather than ignoring them. Use resolution and aspect_ratio instead. Why the 400 happens and how to fix the request.
Webhook not fired when a job is canceled? Jobs vs runs in Sume
A canceled Sume job sends job.canceled, but a canceled run sends no webhook at all. Which surface you called decides it; how to detect a cancel by polling.
Webhook payload too large (1 MiB)? Fetch the result URL
A Sume run receipt over 1 MiB arrives with payload null and a payload_too_large error. The run did not fail; fetch the receipt from result_url. Handler steps.
Webhook endpoint redirect 301 not followed: what Sume does
Sume does not follow redirects on webhook deliveries: a 3xx is a failed attempt, not a delivery. Point webhook_url at the final URL, not a hop.
Webhook dedupe id stable across retries: request_id and created_at
On Sume run webhooks, dedupe on the envelope request_id, which equals run_id and repeats on every retry. Order by created_at; request_id cannot.
Webhook retry: fixed delay vs exponential backoff, with numbers
Fixed delay retries at even gaps; exponential backoff doubles them. Sume uses fixed for job webhooks and backoff for run webhooks: how long each keeps trying.
Webhook unknown event type: return 204, not a 500
One Sume verifier covers run and job webhooks. Route on event and answer 204 for unknown types so a new event never becomes a 500 and a retry storm.
Webhook signature mismatch: compare the secret fingerprint first
When a Sume webhook signature will not verify, compare x-sume-webhook-secret-fingerprint with the dashboard fingerprint. It is safe to paste into a ticket.
Webhook secret rotation: no downtime with a 24-hour window
After you rotate a Sume webhook signing secret, deliveries carry two signatures for 24 hours. What the header looks like and how to redeploy safely.
Webhook send test vs redeliver: which one replays a real job?
Send test posts a dummy webhook.test payload to a URL you type. Redeliver re-sends a real terminal event and does not use one of the automatic 10 attempts.
Webhook status OK but output null? Read outcome: degraded
A Sume run webhook can say status OK while output is null. The run completed and billed; outcome is degraded and output_error says why. How to branch on it.
fal.ai and Replicate alternatives for AI video generation
Alternatives to fal.ai and Replicate for AI video: Kling's and Runway's APIs, Higgsfield, and Sume, compared on price unit, models, API shape and limits.
Text to video API: how it works, what it returns, cost
A text to video API takes a prompt and returns a job id, not a video: poll it or take a webhook, then download the file. Fields, flow and prices.
Text to video and image to video: how they differ
Text-to-video invents every frame from words; image-to-video starts on your picture and animates it. How they differ, and how one request does both.
What is a video API? The five kinds, explained
A video API lets code make, edit or deliver video over HTTP. The five kinds, what each one takes and returns, and how to tell which one you need.
AI model aggregator: what it is and when to go direct
An AI model aggregator sells many labs' models behind one API key, one request shape and one bill. What you gain, what you give up, and what to check.
AI model router: what it does and what you give up
An AI model router picks which model serves each request, so your code sends one id. How that differs from pinning a model, and the control you trade.
API vs SDK: what's the difference, and do you need one?
An API is the contract: routes, fields and errors. An SDK is a library in one language that calls that API for you. What an SDK adds, and when to skip it.
Asynchronous request-reply pattern: how it works
In the asynchronous request-reply pattern, the server accepts work with a 202 and a status URL, and the client polls or takes a callback until it's done.
Rate limit headers: what limit, remaining and reset mean
Rate limit headers report your request budget: the window's limit, what's left, and when it resets. What each means and how a client should pace itself.
HTTP 202 vs 201: created now, or accepted for later?
Return 201 Created when the resource exists by the time you respond, and 202 Accepted when the work will finish later. How 200, 201 and 202 differ.
fal vs Replicate: how calls, webhooks and billing differ
fal and Replicate both run many models behind one async API. fal bills per output and recommends its queue; Replicate bills most models by time.
Does Runway have an API? Yes: how Runway Dev works
Yes. Runway's developer platform has an HTTP API with Node and Python SDKs: start a task, poll it, read the output. Models, routers and costs.
Edit decision list (EDL): what it is, with an example
An edit decision list (EDL) is the ordered list of edits that rebuilds a cut: source, track, transition, and timecodes. An example and its JSON form.
Creatify API: AI avatar videos, Aurora lip sync and credits
The Creatify API makes avatar videos from text or audio, Aurora talking videos from a photo and audio, and ads from a URL, billed in plan credits.
Arcads API: how it works, from credentials to video
Arcads has a public API: Basic auth with a client ID and secret, then a brand, a folder and a script, one generate call, and a poll for the video URL.
MCP server API key vs OAuth: which one to use
Use OAuth when a person signs in from Claude, Cursor, or another client; use an API key header for scripts, CI, and headless runs with no browser.
MCP server file upload: how a local file reaches a tool
A remote MCP server can't read your disk. A tool gets only the arguments your client sends, so the file must sit at a URL the tool accepts.
MCP tool limit in VS Code, Claude Code, and Cursor
VS Code allows 128 enabled tools per chat request. Claude Code has no fixed cap and defers MCP tools. Cursor's MCP docs name no number.
MCP tool exceeds maximum allowed tokens: the fix
Claude Code caps MCP tool output at 25,000 tokens by default. Raise it with MAX_MCP_OUTPUT_TOKENS, or make the tool return less data.
Text to speech API in Java: pick a voice, save the MP3
Call a text to speech API from Java: choose a voice selector and an audio format, POST the text, wait for the job, then write the MP3 to disk.
How to get a public URL for an image an API can fetch
Host the image where anyone can fetch it over HTTPS without a login: a public storage object, a public bucket URL, or your own site. Then test it.