Branded posts and emails, staged for your yes

A social content engine that keeps a posting calendar, makes social graphics from the brand's Canva templates, writes captions in the owner's voice, stages posts in HubSpot and saves email copy as Mailchimp drafts, and never publishes or sends anything itself

The problem

A small business owner knows they should post every week, but designing each graphic, writing the caption and resizing it for every channel takes an evening they do not have, so the feed goes quiet for weeks. When they do post, the voice and the look change every time because nobody keeps a calendar or a brand standard.

How the agent works

1. It starts

   The owner installs Anthropic's open source small-business plugin in Claude Cowork or Claude Code and connects Canva, plus, if they have them, Shopify for product photos and prices, HubSpot for social staging and Mailchimp for email drafts.

2. The agent works

   When the owner says something like 'we've gone quiet on Instagram', the social content engine skill builds or extends a content calendar in which every row is marked either Canva (social graphics only) or text only, and the owner approves it. Before any design is made it states the generation budget (three candidates per row by default) against Canva's rate limit and waits for a yes, then checks every image slot in the chosen Canva template one by one, uploads missing photos and generates one row at a time, looking at each design before showing it. The owner picks one design per row; approved designs are resized for other placements instead of regenerated, and every caption is written against the owner's saved voice profile and approved row by row.

3. The result

   After a final checkpoint, social posts are staged in HubSpot (Marketing Hub Professional) or exported as a scheduling CSV, email copy is saved as a Mailchimp draft campaign, and the skill itself never publishes or sends.

Worked example

The social-content-engine skill in Anthropic's knowledge-work-plugins repository sets five approval checkpoints: the calendar, the generation budget, one design per row, the copy row by row, and a final check before anything is staged. It refuses to restate a price, discount or stock count that Shopify did not return, stops after a second Canva quota error, and never sends email rows to Canva. Its companion canva-creator skill, for a one off campaign from an approved brief, caps the calendar at 30 days unless the brief says otherwise, pauses 30 seconds between rows, writes emails with a subject of 50 characters or fewer and a body of 100 to 250 words, and notes that Canva Pro and Teams accounts have no autofill API, so templates there are copied and edited instead. For the Mailchimp side, the open source mailchimp-mcp-server by damientilman offers create_campaign, set_campaign_content and send_test_email, with MAILCHIMP_DRY_RUN and MAILCHIMP_READ_ONLY flags to stop it writing until you trust it. None of the sources reports a business's results, so track your own: posts published per week and how many drafts you edit before approving.

Sources

• https://raw.githubusercontent.com/anthropics/knowledge-work-plugins/main/small-business/skills/social-content-engine/SKILL.md
• https://raw.githubusercontent.com/anthropics/knowledge-work-plugins/main/small-business/skills/canva-creator/SKILL.md
• https://claude.com/connectors/canva
• https://github.com/damientilman/mailchimp-mcp-server