Hermoso is a marketing MCP server: 850+ tools over one OAuth’d endpoint that let an agent research the ads already running in a market, generate finished image and video ads, publish them, and build the paid campaigns behind them. Gemini CLI reaches all of it through one connection. This page is about one slice of that — what Gemini CLI can actually do on Pinterest, and what Pinterest will not let it do.
Connect Hermoso to Gemini CLI
- Install the extension.
It installs the latest release of Hermoso’s public repository: five skills (research, ad-from-brand, generate, product-photoshoot and marketing) plus agemini extensions install https://github.com/hermoso-ai/hermosoGEMINI.mdcontext file. The skills run thehermosocommand throughnpx, so nothing is added to Gemini CLI’s tool list and nothing costs context until a command runs.gemini extensions listshows them under Agent skills. - Sign in once.
It opens a browser sign-in and stores an owner-only credential innpx -y hermoso auth login~/.hermoso/config.json. Gemini CLI can run it for you the first time it needs Hermoso. No browser on that machine? Create a key under MCP & CLI → Terminal & API keys and runnpx -y hermoso auth login --token hmk_…. - Optional: the MCP server as well.
Gemini CLI finds Hermoso’s authorization server when the first connection answers 401 and registers itself, so no key goes ingemini mcp add --scope user --transport http hermoso https://app.hermoso.ai/mcpsettings.json;/mcp auth hermosoinside a session runs the sign-in. The skills reach every tool without it. - Ask Gemini CLI for something. “Pull my three closest competitors’ longest-running ads and remix the best hook into a 9:16 video,” or “post this render to the channel.” The agent picks the tools; you approve the spend.
We ran the install above on 2026-09-23 against Gemini CLI 0.60.0 in a clean home directory: it pulled the current release of hermoso-ai/hermoso, and gemini extensions list reported the five skills and the context file. The extension carries no MCP server of its own, which is deliberate: a tool list is loaded into every session, and skills cost nothing until they run. Hermoso is not affiliated with or endorsed by Google.
Then connect Pinterest itself, once, under Settings → Connectors in Hermoso. That is an OAuth consent screen, so it is the one step that needs a browser — everything after it is a tool call.
The Pinterest tools Gemini CLI gets
list_pinterest_boards— the account’s boards, including secret ones, with their ids.create_pinterest_board— makes a new board.post_to_pinterest— creates an image or video Pin on a board you name, with a title, a description, a destination link and alt text.schedule_post— queues the Pin, carryingboardId.list_pinterest_ads_campaigns / pinterest_ads_report— read the paid side.
The limit you need before you plan a Pinterest workflow: this app holds Trial access, and Pinterest refuses Pin creation in production on Trial. Their words, caught on the first real Pin: “Apps with Trial access may not create Pins in production.” Boards and reads do work on Trial — listing boards, creating boards, reading Pins — and Hermoso’s error names the access tier rather than telling you to reconnect, because reconnecting cannot fix it. An upgrade to Standard access is what unblocks Pin creation, and it is pending review. The same tier limits the paid side: on Trial, Pinterest exposes no ad accounts at all.
Pinterest limits worth knowing before you automate anything
| Text | A Pin description is capped at 800 characters and a Pin title at 100. It is enforced when the post is created or queued — refused while you are still there to fix it, rather than silently cut on the way out. |
|---|---|
| Visibility | Public, and the control is the board rather than the Pin. A Pin inherits its board’s public or secret state, so “post it somewhere private” is expressed by choosing a secret board — which is why the board is a required argument rather than a default. |
| Carousel | 2 to 5 images, images only. Both bounds come straight from Pinterest’s own v5 OpenAPI (minItems: 2, maxItems: 5), which is the only machine-readable source Pinterest publishes — their developer site is a client-rendered app that returns nothing to a fetch. There is no multi-video source, so a video slide is refused rather than dropped. |
| Which account | boardId, and it is the only identity field refused at enqueue rather than at publish time: “A Pin has to go on a board — pass boardId. Nothing was scheduled: a Pin on the wrong board is a public mistake, so we never choose one for you.” |
Try it in Gemini CLI
Ask for it in ordinary language — these are sentences, not a DSL:
“Create a board for the autumn range, generate six vertical Pin images with titles and descriptions, and write the set to ./out/pins.json.”
That walks list_pinterest_boards → plan_ad → generate_image → post_to_pinterest. Gemini CLI asks before it runs a shell command, and the skills act through the hermoso command, so a publish shows up as a line you can read before you say yes. For MCP tools it offers once, always for that tool, or always for the server.
Gemini CLI on Pinterest: the part that bites
Stage the Pins as data now. Boards list and create on Trial access; Pin creation is refused in production by Pinterest itself, and no retry changes an access tier. When Standard access lands, the file you staged is the batch. boardId is required and refused at enqueue when missing, because a Pin on the wrong board is a public mistake.
Two Gemini CLI details decide how safe this is. gemini mcp add writes to the project’s .gemini/settings.json unless you pass --scope user, which is useful when one repo should always run against one brand. And never add Hermoso with --trust: it skips every confirmation for the server, including the ones in front of a publish. MCP tools arrive named mcp_hermoso_ plus the tool name, and --exclude-tools keeps any of them out entirely.
Research Pinterest before you post
There is no Pinterest ad library, so competitor research on Pinterest is not something Hermoso claims. The creative you would run there is well covered by the rest of the studio — make_template_ad and the image models produce the vertical, text-forward stills the surface rewards.
The paid half
Pinterest Ads tools exist — campaign, ad group and an ad that promotes an existing Pin, and archiving rather than deleting, because Pinterest’s ADS API has no delete verb (organic Pins and boards do delete, through delete_pinterest_pin and delete_pinterest_board; it is the paid objects that can only be archived). But the same Trial-access tier that blocks Pin creation exposes no ad accounts, so ad writes are not usable until Standard access lands. That is the honest state, and it is better in a sentence here than discovered on a deadline.
What Gemini CLI cannot do on its own
An agent with a budget is only useful if the blast radius is bounded, so the fence is in the server rather than in a prompt. Every ad campaign, ad set, ad group and ad is created paused, and the status switches that arm real money refuse to run without an explicit confirmation flag. Every render is quoted first — hermoso_capabilities publishes each model’s exact credit cost before anything spends — and credits are reserved before the first provider call and settled at the exact cost afterwards, so a failed dispatch refunds rather than leaving you billed for nothing. Deletes are confirm-gated too, and every campaign tree is read back from the ad platform before your agent tells you what it built.
One step is deliberately not headless: linking an account is an OAuth consent screen, so you connect the channel once in a browser. Everything after that is a tool call.
The rest of the matrix
From Gemini CLI, post to: Facebook · Instagram · Threads · TikTok · YouTube · X · LinkedIn · Bluesky · Telegram — or see everything Gemini CLI can publish to.
Post to Pinterest from: Claude · ChatGPT · Claude Code · Cursor · Codex · Cline · OpenClaw · Grok Bot · Hermes · Perplexity · Le Chat
Frequently asked questions
Can Gemini CLI post to Pinterest?
Yes, with Hermoso's Gemini CLI extension. Run gemini extensions install https://github.com/hermoso-ai/hermoso, which adds five Hermoso skills that drive the hermoso command, then sign in once with npx -y hermoso auth login. The sign-in opens a browser and stores the credential itself, so there is no key to create and none to paste. If you also want Hermoso's tools in Gemini CLI's own list, gemini mcp add --scope user --transport http hermoso https://app.hermoso.ai/mcp adds the hosted server, which signs in with OAuth. Gemini CLI then has 850+ tools, including the ones that publish to Pinterest — and the ones that research the ads already running in your market and render the creative in the first place.
How do I connect Pinterest to Gemini CLI?
Two steps, once each. Run gemini extensions install https://github.com/hermoso-ai/hermoso, which adds five Hermoso skills that drive the hermoso command, then sign in once with npx -y hermoso auth login. The sign-in opens a browser and stores the credential itself, so there is no key to create and none to paste. If you also want Hermoso's tools in Gemini CLI's own list, gemini mcp add --scope user --transport http hermoso https://app.hermoso.ai/mcp adds the hosted server, which signs in with OAuth. Then connect Pinterest inside Hermoso under Settings → Connectors, which is an OAuth consent screen in a browser. After that Gemini CLI publishes to Pinterest as an ordinary tool call.
What is the Pinterest caption limit when posting from Gemini CLI?
A Pin description is capped at 800 characters and a Pin title at 100. Hermoso enforces it when the post is created or queued, so Gemini CLI is told immediately rather than failing later when nobody is watching.
Can Gemini CLI research Pinterest before it posts?
There is no Pinterest ad library, and Hermoso does not claim competitor research there. The rest of the research surface — Meta, Google and LinkedIn ad libraries plus organic TikTok, Instagram, YouTube, Reddit and Threads — is unaffected.
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