PostNitro

PostNitro — Create & Schedule Social Posts

PostNitro creates on-brand social media posts — multi-slide carousels, single images, and short videos — and schedules them across LinkedIn, Instagram, TikTok, and Threads. This skill drives it from the command line, so an agent can take a topic, article, or your own content and produce a finished, scheduled post in one workflow. Every command is JSON in / JSON out — safe to script and chain.

Setup

1. Install the CLI:

   npm install -g @postnitro/cli
   

2. Sign up at https://postnitro.ai and subscribe to a plan — the Embed API requires a paid subscription (no free tier). Then generate an API key at account settings → Embed → Generate API Key.
3. Authenticate (in order of precedence: --api-key flag → env var → saved config):

   postnitro auth set-key pn-xxxx        # persists to ~/.postnitro-cli/config.json
   export POSTNITRO_API_KEY="pn-xxxx"    # or use an env var
   

4. Save defaults so you don't repeat template/brand/preset IDs on every call (the CLI's alternative to per-call flags — no env vars needed):

   postnitro defaults set --template-id  --brand-id  --preset-id  --response-type PDF
   

Key rule: carousel generate/import return an embedPostId (the async job). To schedule the result you need its designId (from the --wait output or carousel output). Never pass an embedPostId to schedule.

Security: auth set-key stores your API key in plaintext at ~/.postnitro-cli/config.json. Restrict its file permissions and avoid shared or untrusted machines; run auth clear to remove it. This skill runs no background processes, cron jobs, or startup scripts — the only local state is the API key and saved defaults, both disclosed above.

When NOT to use: as a general social-media strategy advisor when no content is being produced. (PostNitro composes with other tools — e.g., create a carousel here, then schedule it elsewhere — so pairing it with another scheduler is fine.)

Core Workflow

Every create command is asynchronous — --wait handles the polling and returns the finished output (including designId and editorUrl) in one call.

1. Create a post

Two independent choices decide which command you run:

• Post type — a multi-slide carousel, a single image, or a video.
• Content source — let AI write it (generate) or supply your own (import).

That's six commands:

All six take --template-id/--brand-id (from flags or saved defaults) plus the modifiers in step 2, and every result includes the designId (needed to schedule) and an editorUrl.

AI-generated (generate)

postnitro carousel generate \
  --context "5 tips for growing your LinkedIn audience in 2026" \
  --type text \
  --instructions "Professional tone, actionable advice" \
  --wait

# Single image instead — same flags, just the image subcommand
postnitro image generate --context "Announce our new scheduling feature" --wait

# Video — same flags, plus the render length when you want the MP4 back
postnitro video generate --context "3 habits that make remote teams faster" \
  --response-type MP4 --video-duration 30 --wait

--type values:

• text — --context is the topic/text to turn into a post
• article — --context is an article URL to extract and convert
• x — --context is an X (Twitter) post/thread URL

generate also needs an AI preset (--preset-id, or a saved default).

Import your own content (import)

# Carousel — slides is an ARRAY of typed slides (inline --slides overrides --file)
postnitro carousel import --slides '{"slides":[
  {"type":"starting_slide","heading":"Your Title","description":"Intro text"},
  {"type":"body_slide","heading":"Key Point","description":"Details here"},
  {"type":"ending_slide","heading":"Take Action!","cta_button":"Learn More"}
]}' --wait
postnitro carousel import --file ./slides.json --wait

# Single image — slide is a SINGLE OBJECT (not an array), via --slide
postnitro image import --slide '{"heading":"Welcome!","sub_heading":"Subtitle","cta_button":"Learn more"}' --wait

# Video — same slide ARRAY as a carousel; each slide is a scene
postnitro video import --file ./scenes.json --response-type MP4 --video-duration 30 --wait

• Carousel (--slides, array): exactly 1 starting_slide (first), ≥1 body_slide, exactly 1 ending_slide (last); heading required on every slide. Run postnitro carousel import-template for the schema. Ready-to-use: examples/import-default.json, examples/import-infographics.json.
• Image (--slide, one object): fields heading (required), sub_heading, description, cta_button, image, background_image (plus infographic — see step 2). Sending an array here is rejected. Run postnitro image import-template for the schema.
• Video (--slides, array): the carousel rules exactly — each slide becomes a scene, in order. Run postnitro video import-template for the schema and the render settings.

2. Options for any create command

These layer onto any of the four commands above (and onto generate-and-schedule).

Output format — --response-type PDF | PNG | DESIGN | MP4

Default PDF (single file URL). PNG returns one URL per slide. DESIGN skips rendering — no file is produced; you get just the designId + editorUrl, the fastest option when you only need to schedule or edit.

MP4 (single video URL) belongs to video only, and a video accepts nothing but MP4 or DESIGN — never PDF/PNG. Video commands default to DESIGN, so pass --response-type MP4 when you want the file. MP4 also can't be stored via defaults set, since it would break carousel and image calls.

Video length & audio — video only

postnitro audio list                       # find an audio track's ID
postnitro video generate --context "..." --response-type MP4 --video-duration 30 --audio-id  --wait

• --video-duration — the whole video's length, not per scene. At least 5 and under 60. Required with --response-type MP4; optional for DESIGN (set it later in the editor).
• --audio-id — an audio ID from postnitro audio list, never a URL. Omit for a silent video. Uploading audio happens in the PostNitro app; the CLI can list (audio list) and delete (audio delete --yes) but not upload.
• Rendering a video takes longer than a carousel — typically 15-45s with --wait and MP4, longer for designs with animations or GIFs.
• These same settings are reused automatically when the video is later scheduled as a reel.

AI image generation — --generate-images (any post type, any source)

Opt in to have AI generate images and bake them into the design before rendering. Works on all six create commands (and both one-shot commands) — carousels, images, and videos alike. Requires an --image-context brief:

postnitro carousel generate --context "How scheduling saves marketers time" \
  --generate-images --image-context "upbeat and professional, product-focused" \
  --image-placement auto --image-strategy all --wait

• --image-context — required when generating images: a short visual brief for the image prompts
• --image-placement auto|background|in-line (default auto — AI decides per slide)
• --image-strategy strategic|all (strategic ≈ 50% of slides, default; all = every eligible slide)

Best-effort: the post still completes if images fail or aren't permitted. With --wait, the result carries an imageGeneration field (the GENERATE_IMAGES step); if its status is FAILED, its message explains why (e.g. free plan can't generate AI images, or the org is over its AI-image quota). AI images bill against the org's separate AI-image quota, not the post's slide credits, and add latency. Without --wait, the same step shows up in status logs.

Infographic layout — import only

On either import command, set layoutType: "infographic" on a slide (with a layoutConfig) to render data columns (max 3) instead of an image. Every column and content item needs a caller-provided id, and each item description is an HTML string. See carousel import-template / image import-template for the full schema.

3. Check status / get output (only if you didn't use --wait)

postnitro carousel status    # progress + step logs; poll until COMPLETED
postnitro carousel output    # final file URL(s) + designId + editorUrl

(image status / image output and video status / video output work identically for those post types.)

Output is a PDF (single URL), PNG (one URL per slide), or MP4 (single URL) in data, plus the designId and editorUrl. Those can be handed to another tool — e.g. a different scheduler — to publish on platforms PostNitro doesn't cover. With --response-type DESIGN there's no rendered file, so data/mimeType/outputType are omitted (you still get designId and editorUrl).

4. Schedule the design to social accounts

postnitro social list   # get account IDs + platforms

postnitro schedule create \
  --status SCHEDULED \
  --scheduled-at "2026-12-31T13:00:00Z" \
  --design-id  \
  --selected-accounts '[""]' \
  --linkedin-post-settings '{"postType":"document","postTitle":"5–90 char title"}' \
  --post-content '{"common":"Caption with #hashtags"}'

5. One-shot: create + schedule

Create and schedule in a single call — generate-and-schedule (AI writes it) or import-and-schedule (your own content). Both accept the schedule flags from step 4, --post-type CAROUSEL|IMAGE|VIDEO (with --video-duration/--audio-id for a video), and the AI-image options from step 2. If creation succeeds but scheduling fails, the error returns the designId so you can retry schedule create without re-creating (or re-spending credits).

# AI-generated
postnitro generate-and-schedule \
  --context "topic" --type text \
  --status SCHEDULED --scheduled-at "2026-12-31T13:00:00Z" \
  --selected-accounts '[""]' \
  --linkedin-post-settings '{"postType":"document","postTitle":"..."}' \
  --post-content '{"common":"..."}'

# Your own content — --slides (carousel array) or --slide (single image); --slides-file for a file.
# (Here --file is the SCHEDULE body, so slides come from --slides / --slides-file.)
postnitro import-and-schedule \
  --slides '{"slides":[ ... ]}' \
  --status SCHEDULED --scheduled-at "2026-12-31T13:00:00Z" \
  --selected-accounts '[""]' \
  --post-content '{"common":"..."}'

Common Patterns

Pattern 1: LinkedIn thought-leadership carousel

postnitro carousel generate \
  --context "5 mistakes startups make with their LinkedIn strategy and how to fix each one" \
  --type text --instructions "Professional but conversational. One clear takeaway per slide." --wait

Pattern 2: Repurpose a blog post

postnitro carousel generate --context "https://yourblog.com/posts/social-media-strategy-2026" \
  --type article --instructions "Extract the 5 most actionable points. Keep slide text concise." --wait

Pattern 3: Repurpose an X thread

postnitro carousel generate --context "https://x.com/username/status/1234567890" \
  --type x --instructions "Maintain the original voice and key points" --wait

Pattern 4: Data-driven infographic carousel

Import slides with layoutType: "infographic" body slides — see examples/import-infographics.json.

Pattern 5: Video reel with an audio track

AUDIO=$(postnitro audio list | jq -r '.audios[0].id')
postnitro video generate --context "3 habits that make remote teams faster" --type text \
  --response-type MP4 --video-duration 30 --audio-id "$AUDIO" --wait

A reel reuses the video's own duration and audio when scheduled, so --post-settings is optional — omit it and the API fills it in (falling back to 30s with no audio).

Pattern 6: Audit one account's schedule

LINKEDIN=$(postnitro social list | jq -r 'first(.accounts[] | select(.platform=="linkedin").id)')
postnitro schedule list --from 2026-09-01 --to 2026-09-30 --accounts "$LINKEDIN"

--accounts filters the posts, not the accounts inside them: a post targeting LinkedIn and Instagram is returned when you filter by either, and it still lists both accounts.

Pattern 7: Generate → schedule to LinkedIn

DID=$(postnitro carousel generate --context "5 remote work habits" --type text --wait | jq -r .designId)
LINKEDIN=$(postnitro social list | jq -r 'first(.accounts[] | select(.platform=="linkedin").id)')
postnitro schedule create --status SCHEDULED --scheduled-at "2026-12-31T13:00:00Z" \
  --design-id "$DID" --selected-accounts "[\"$LINKEDIN\"]" \
  --linkedin-post-settings '{"postType":"document","postTitle":"5 remote work habits"}' \
  --post-content '{"common":"New carousel 🚀 #remotework"}'

Pattern 6: Batch scheduling

DATES=("2026-02-14T09:00:00Z" "2026-02-15T09:00:00Z")
TOPICS=("Monday motivation 💪" "Tuesday tips 💡")
for i in "${!DATES[@]}"; do
  postnitro generate-and-schedule --context "${TOPICS[$i]}" --type text \
    --status SCHEDULED --scheduled-at "${DATES[$i]}" \
    --selected-accounts '[""]' \
    --linkedin-post-settings '{"postType":"document","postTitle":"Daily post"}'
done

Content Strategy Tips

• LinkedIn: professional tone, actionable insights, 6–10 slides, clear CTA. PDF carousels post as postType: "document" (needs a 5–90 char postTitle).
• Instagram: visual-first, concise text, 5–8 slides, storytelling arc. postAsStory for stories.
• TikTok: trendy, punchy, 4–7 slides, hook on slide 1.
• X / Threads: data-driven, 3–6 slides, provocative opening.

Common Gotchas

1. Not authenticated — run postnitro auth status; set a key before anything else.
2. Scheduling with embedPostId — use the designId from --wait/carousel output, never the embedPostId.
3. Scheduled at is in the past — --scheduled-at must be a future ISO-8601 datetime with a trailing Z.
4. Invalid inline JSON — wrap JSON flags in single quotes; the CLI validates before any network call.
5. Missing --brand-id ... multiple candidates — pass the ID or save a default with defaults set.
6. LinkedIn document rejected — postType:"document" needs a 5–90 char postTitle.
7. Empty post — a scheduled post needs either --design-id or non-empty --post-content.
8. Destructive commands — social disconnect and schedule delete require --yes.
9. SCHEDULED publishes live — use DRAFT when unsure; confirm time/account with the user first.
10. responseType — the CLI defaults to PDF (pass --response-type PNG for individual slide images, or DESIGN to skip rendering and only create the design). Note: the underlying API now defaults to DESIGN when omitted, but the CLI always sends PDF explicitly, so CLI behavior is unchanged.
11. Credits vary — AI generation ≈ 2 credits/slide; content import ≈ 1 credit/slide. Warn before large batches.

Credits & Pricing

The Embed API requires a paid subscription — there is no free tier, and free accounts cannot call the API. See https://postnitro.ai/plans for current plans and credit allowances.

Approximate usage cost (observed):

• Content import: ~1 credit per slide
• AI generation: ~2 credits per slide

Supporting Resources

In this skill:

• references/cli-reference.md — complete command, platform-settings, and slide-schema reference
• examples/EXAMPLES.md — ready-to-use import & schedule JSON (import-default.json, import-infographics.json, schedule-post.json)

Full project docs (GitHub):

• README — full command reference
• QUICK_START.md — zero to a scheduled carousel in minutes
• HOW_TO_RUN.md — install & run methods
• PLATFORM_SETTINGS.md — platform settings schemas
• FEATURES.md — full feature list
• Per-command help: postnitro --help

Quick Reference

# Auth (do this first)
postnitro auth set-key pn-xxxx | postnitro auth status | export POSTNITRO_API_KEY=pn-xxxx

# Discover + defaults
postnitro template list | brand list | preset list | social list
postnitro defaults set --template-id  --brand-id  --preset-id  --response-type PDF

# Create (async — use --wait; result has designId + editorUrl)
# --response-type PDF|PNG|DESIGN (DESIGN skips rendering; CLI default is PDF)
# Optional AI images (any generate/import): --generate-images --image-context "brief" [--image-placement auto|background|in-line] [--image-strategy strategic|all]
postnitro carousel generate --context "topic|url" --type text|article|x [--instructions "..."] --wait
postnitro carousel import (--slides '{"slides":[...]}' | --file ./slides.json) --wait
postnitro carousel status         # if not using --wait
postnitro carousel output         # file URLs + designId + editorUrl

# Single-image posts (mirror carousel; import takes ONE slide object, not an array)
postnitro image generate --context "topic|url" --type text|article|x --wait
postnitro image import (--slide '{"heading":"..."}' | --file ./slide.json) --wait

# Schedule (date REQUIRED + future; use designId, not embedPostId)
postnitro schedule create --status SCHEDULED|DRAFT --scheduled-at "" --design-id  \
  --selected-accounts '[""]' --linkedin-post-settings '{"postType":"document","postTitle":"..."}' \
  --post-content '{"common":"caption"}'
postnitro schedule list --from "" --to "" | get  | delete  --yes

# One-shot: create + schedule (both take --post-type + AI-image flags)
postnitro generate-and-schedule --context "topic" --status SCHEDULED --scheduled-at "" ...
postnitro import-and-schedule --slides '{"slides":[...]}' --status SCHEDULED --scheduled-at "" ...   # or --slide for image

Tips for the Agent

• Always confirm authentication (postnitro auth status) before running any other command. Never fabricate an API key — ask the user.
• Prefer --wait so one call returns the finished output and designId.
• Discover IDs with the list commands; save workspace defaults with defaults set so later calls stay short.
• Schedule with the designId, not the embedPostId.
• For --type article/x, --context must be a URL. For plain text, use --type text.
• responseType defaults to PDF in the CLI — pass --response-type PNG for individual slide images, or DESIGN to skip rendering when you only need the designId/editorUrl (e.g. for scheduling).
• --scheduled-at must be a future ISO-8601 datetime (trailing Z).
• status: SCHEDULED creates a live post that will publish — confirm the time and account with the user, or use DRAFT when unsure.
• Parse stdout as JSON; on failure read .error.message from stderr and fix the inputs.
• Warn about credit costs before large batches (AI generation is ~2× the cost of import).
• If the user doesn't specify a platform, suggest LinkedIn (most common carousel use case) and remember PDF carousels post there as document.