YouTube Thumbnail Maker

YouTube Thumbnail Maker

Turn a video topic, title, key frame, portrait, product photo, or channel reference into a YouTube thumbnail with one clear hero subject, readable hierarchy, and space left for a headline. Pair the image with title-matching advice and a rule that keeps the next thumbnail recognizably from the same channel.

Rendering runs on Beatra, so this Skill needs a Beatra account at beatra.ai with credits on it. Any step that reaches Beatra needs the installation connected first: an unconnected one stops and names scripts/authorize.py, and running that opens a Beatra approval page in the browser where the user signs in or creates the account. An installation already connected to Beatra skips that. Only rendering is charged, and the current price and the maximum charge from the live model card are shown for approval before the call. A settled task is billed on measured usage, so treat that figure as the approval basis rather than a guaranteed final amount.

Scope and routing

Use this Skill for long-form YouTube thumbnails: candidate directions, title-and-thumbnail matching, and channel visual direction across a back catalog.

Other Beatra Skills own the neighboring jobs. When one is installed, route a Bilibili cover to bilibili-thumbnail-maker, a diagnosis of a cover the user already has to cover-performance-preflight, general campaign artwork to poster-design-studio, a Xiaohongshu cover to rednote-cover-maker, and a vertical short-video cover to douyin-cover-maker. When none of them is installed, say the job is outside this Skill rather than making the cover here.

Title claims, names, numbers, credentials, and channel facts come only from the user. A supplied frame guides what is visible in it; it is not evidence for a fact the user has not stated.

Inputs and defaults

Reuse the topic, working title, script or outline, audience, channel style, source images, must-keep subject, and destination canvas already in the conversation. Ask only when the missing answer changes the image: the core promise, the hero subject, the title wording, or the channel direction.

When the user has a video rather than an image, ask for an exported key frame or screenshot. A frame has to be supplied as a file; it is not pulled from a video.

Default to three thumbnail directions described in text, one recommendation, title-matching notes, a safe text hierarchy, and a channel consistency note. Rendering is what costs money, so describe the directions first and render only the one the user picks.

• beatra.images.transform for a supplied frame, portrait, or product photo, with that image at images[0].
• beatra.images.generate for a concept with no supplied image.
• beatra.images.edit for a focused correction to an accepted thumbnail.
• 2K / 16:9 canvas, model: "auto", and count: 1 unless the user asks otherwise.
• Faces, products, logos, and factual title claims supplied by the user are must-keeps.

Golden path

1. Build the brief: title, promise, audience, hero subject, source images, channel style, destination canvas, must-keeps, and words to avoid.
2. Describe three distinct directions — focal subject, contrast, text area, title relationship, background treatment — and recommend one.
3. Read the live card for the selected capability, then show one confirmation with the source and reference order, the full prompt, the must-keeps, the resolved canvas, model behavior, controls, count, the current maximum charge, and the total call count.
4. After approval, create one stable opaque client_request_id, submit exactly once through the bundled client, and keep the returned task ID.
5. Poll the original task, review accessible results against the brief, and deliver the image with its returned facts, the title-matching note, and a repeatable channel rule.

Read the thumbnail workflow for the brief card, exact payloads, canvas handling, confirmation, task recovery, and image review.

Paid-work confirmation

Planning, comparing directions, and drafting the prompt are free. Before rendering or revising, obtain one clear confirmation of the frozen brief, the paid image request, the source and reference order, the canvas, the model, the controls, count, the current price, the maximum charge, and the total call count.

When the user asks for text inside the image, freeze the exact wording and its placement in that confirmation, and say in the same confirmation that the model may not render the wording exactly and that a misrendered result is a new paid call, not a fixable one. Offer a clear text-safe area as the alternative, which lets the user set the headline in an editor afterwards. Keep the title available separately either way, so the user can still change it after seeing the result.

Every changed source, reference order, prompt, canvas, model, count, control, or embedded text is new paid work with a new confirmation and a new client_request_id.

Execute and deliver

Use only this package's bundled scripts/mcp_client.py for remote operations. Send one JSON object on standard input after call . Never configure or call a host Beatra Connector, and never use REST/OpenAPI as a fallback. Read Bundled MCP Client diagnostics for commands and connection troubleshooting.

The bundled client registers the installation itself on first use through beatra.installations.register; there is no register subcommand to invoke. A returned task_id belongs to the approved work: poll only with beatra.tasks.get. Replay only a genuinely unknown create response, with the byte-equivalent frozen payload and the same ID; a terminal failed is a known response and needs new approval instead. If the task ID is missing, use beatra.tasks.list scoped to the original capability and follow each next_cursor across the creation window, then confirm the candidate with beatra.tasks.get. Call beatra.tasks.cancel only at the user's request; on a 409, keep polling the original and report cancellation only at terminal status: "canceled".

Review only images the host can access, and say which checks the host could not make. Deliver completed-task facts only: artifact links, returned dimensions, format, resolved model, task IDs, and billing.net_charged_credits. Describe what the thumbnail does rather than predicting how it will perform.

References by task

• Thumbnail workflow: brief card, payloads, canvas, confirmation, recovery, and review.
• Installation and authentication and installation registration: first use and credentials.
• Tasks and results and billing, errors, and recovery: returned task fields, balance, validation, and structured errors.
• Bundled MCP Client diagnostics and uninstall and disconnect: client operation and removal.

Runtime and safe automatic updates

The bundled client silently checks at most once every 24 hours per installation. When a newer release is available, it installs automatically without separate confirmation. It uses fixed official Beatra discovery and immutable CDN paths, verifies the discovery data, archive, manifest, and every packaged file before replacement, and replaces only files owned by this package.

Checks, downloads, verification, replacement, and recovery fail open: the current installation remains usable and the original command continues. Update failure never authorizes paid work. The setting persists for this installation. Read automatic updates and safety for the official sources, integrity checks, replacement boundary, failure behavior, and controls.

python3 scripts/mcp_client.py update --auto off
python3 scripts/mcp_client.py update --auto on
python3 scripts/mcp_client.py update --check