01
Before: three drafts, three voices, none of them right
- Reddit downvotes anything that smells like a press release.
- LinkedIn punishes Reddit slang and short, dry text.
- X cuts your headline in half and reposts a screenshot instead.
Case 02
Reddit, LinkedIn, X. Three voices in one agent.
02
What you do in Claude Code
One agent, three voice sets, all in the same chat.
- 01 Add Prostir as an MCP server in Claude Code.
Same one-time sign-in as case 01.
- 02 Paste in six reference posts: two that worked on Reddit, two on LinkedIn, two on X.
Claude Code labels them per platform and saves each as its own knowledge source.
- 03 Tell it: build me a social writer that picks the voice per channel automatically.
It calls prostir_agents_build with three platform sets and a routing rule in the system prompt.
- 04 Ask for a length check.
Claude Code adds a small JavaScript tool that catches posts longer than X's character limit or shorter than Reddit's minimum.
- 05 Publish.
Your link: prostir.build/yourhandle/three-feeds. Add it once to ChatGPT, Claude, or Codex CLI. Same thing.
03
The reference sets the agent actually reads
Each set is a small batch of real posts that landed on that exact platform.
doc reddit/voice-rules.md Lowercase, no marketing words, story first.
doc reddit/two-strong-posts.md Upvoted threads with the hook noted.
doc linkedin/voice-rules.md Short lines, contrarian opener, soft call.
doc linkedin/two-strong-posts.md Wide-reach posts with the hook tagged.
doc x/voice-rules.md Under 280 chars, no list emojis, one strong noun.
doc x/two-strong-posts.md High-engagement posts inside the limit.
04
Building it inside Claude Code
One chat, one agent, three voice sets.
Build me a social writer on Prostir that picks the voice when I name the platform. I'll paste six reference posts here.
prostir_agents_design_interview Confirming: one agent, three platform sets (reddit, linkedin, x), routing inside the system prompt. Add a length check tool? Recommended.
Yes. Block AI tells like unlock and in-today's-fast-paced-world.
prostir_agents_build Created the agent, attached six knowledge files (two per platform), added length_guard.js, wired the routing rules, published to /yourhandle/three-feeds. ✓ Done.
Try: a LinkedIn post about how I shipped this in five minutes. The router picks the LinkedIn voice, the length tool checks the length, banned words get blocked at draft time.
05
After: one prompt, the right voice for the platform
- You type a Reddit reply for r/SaaS about onboarding. Reddit voice, no marketing slop.
- You type a LinkedIn post, contrarian opener, 800 chars. LinkedIn voice, hook first, soft call.
- Your assistant opens the same link. Same voice sets. No more pasting three prompts in a row.
What gets published
One published agent at your own link. You type the platform and the angle. The agent picks the matching voice set, drafts the text, and flags posts that break that platform's format.
Ready to launch?
One afternoon from idea to live link.
Upload what only you have. Write the rules in plain language. Open the link in ChatGPT, Claude, or your site. Ship the agent only you could ship.
Need custom scale, white-label, or dedicated setup? Talk to sales.