Compose Email

Help the user create or edit an email template using Nitrosend's section-based email designer.

Understand the Goal

Ask what the email is for:

• Newsletter / announcement
• Welcome email
• Promotional / sale
• Product update
• Event invitation
• Transactional (receipt, confirmation, etc.)
• Re-engagement

Design the Email

The complete section registry and prop schemas returned by the intent scaffold or nitro://schema are authoritative. Do not reconstruct that registry from this skill. Illustrative section patterns include:

Durable Design Guidance

• Front-load the subject's value and make the preheader complementary.
• Prefer a clear hierarchy and one primary action.
• Design mobile-first, use readable type, descriptive alt text, and adequate contrast.
• Include a footer. Nitrosend supplies the active Brand's canonical legal identity and unsubscribe URL.

Composition Contract

Newly authored copy or full sections always enter the composition contract before persistence:

1. Call nitro_manage_template with composition_mode: "intent" and the user's goal and constraints.
2. Treat next_call.input as the selected complete baseline. Preserve its structure and fill it rather than replacing it with a smaller handcrafted layout. composition_contract.creative_routes is the route menu.
3. To use a different ready route, start a fresh intent with its creative_route_id. If a route reports missing evidence, obtain exactly those facts; never substitute another route or invent evidence.
4. Author inside the returned scaffold while preserving the contract, bindings, exact user constraints, and idempotency fields. Optionally call composition_mode: "validate"; persist with composition_mode: "draft".

Alternatively, request server-side authoring via the returned metered composition_mode: "generate" call, which composes, validates, and persists one draft. Supplying creative fields without a contract returns the intent contract instead of silently creating anything. Only mechanical section_updates — shallow prop/style tweaks on allowed visual attributes — and clones without creative overrides skip recomposition. text_patch copy edits are copy changes: they enter the composition contract like any other new copy.

Full section authoring is an intentional escape hatch, not the default. For an image-led route, follow next_call.image_choice. Use a described Brand Library asset or exact operator asset when available. Otherwise obtain a verified vendor, generated, or public stock asset, ingest it when needed, and reissue the intent with the exact image_url plus an accurate statement of what it shows. Brand memory can guide selection but cannot prove an image URL or its contents.

Create or Update

New template: Use nitro_manage_template with sections array and subject (via the composition contract above).

Update existing: Use nitro_manage_template with template_id and the fields to change — prefer section_updates for targeted edits, and pass if_version for optimistic concurrency (the call is rejected if the template version has moved).

Update a campaign's email: Use nitro_compose_campaign with campaign_id, mode: "patch" and the same section_updates, plus if_version. A campaign's email is saved through its campaign, never through nitro_manage_template.

Clone existing: Use nitro_manage_template with based_on (source template ID); creative overrides enter the authoring contract.

Every non-dry-run persistence mutation — create, clone, targeted update, full update — requires an idempotency_key; contract drafts reuse the stable key carried by the returned next_call.

Always set a descriptive name for the template.

Images

Host images on Nitrosend storage with nitro_ingest (V1 is image-only):

• Small local or chat-attached images: pass image_data
• Larger local files: request a direct upload with upload: {kind, filename, content_type, byte_size, checksum}, PUT the bytes to the returned direct_upload.url sending exactly the returned direct_upload.headers, then call nitro_ingest again with the signed_id
• Public remote image URLs: use directly in sections when permanence is not needed, or pass as image_url for a Nitrosend-hosted copy

Always pass an accurate description to nitro_ingest; it is retained with the Brand Library asset and used as alt-text context. image_data accepts PNG, JPEG, or WebP under the live tool's decoded-size limit. Direct upload checksum is base64-encoded MD5.

The returned hosted URL (media_url/image_url) is what goes into the image section's src — never place a signed_id directly in sections.

Preview and Test

After creating/updating:

1. Use nitro_review_delivery with target_type: "template" and target_id to review content, validate, and check delivery readiness
2. Ask if they want a test email sent
3. If yes, use nitro_send_test_message with target_type: "template", target_id, and an idempotency_key (reuse the same key on retry to avoid duplicate test sends) — sends to saved test recipients or specify explicit recipients with to

Merge Tags

Use canonical personalization variables:

• {{ contact.first_name }}, {{ contact.last_name }}, {{ contact.email }}
• {{ unsubscribe_url }} — required in marketing emails
• {{ event.* }} for flow-event values allowed by the returned composition bindings
• {{ data.* }} only where the returned composition contract permits it