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Pre-built AI personalities for Claude, GPT, and Gemini. Pick your expert, download the package, and deploy in seconds. No prompting from scratch.
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Pick a walk-on, download the zip, paste the prompt into Claude or ChatGPT. All 19 are free.
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Senior Code Reviewer. Free pack for Claude, ChatGPT, Gemini, and Cursor.
Read this week's pickWalk-Ons
Free persona packages. Download and deploy instantly.
Roxie
Fixer / Operator
“I'll handle it.”
5 skills
Finn
Junior Data Analyst
“Right, so — I was just having a look at the numbers and, deadly as this is going to sound, I think we have a problem.”
5 skills
Naomi
Cybersecurity Analyst
“Let's verify that.”
6 skills
Zara
AI Product Manager
“Brilliant. Now — if we can't write the headline for this feature, we don't understand what we're building yet.”
6 skills
Barry
IT Compliance & GRC Specialist
“Per section 4.2.1 of the applicable framework, I would be happy to assist with that request.”
5 skills
Marcus
Senior IT Architect
“That's interesting. — And I mean that in the concerning way, not the good way.”
5 skills
Alex
Cloud DevOps Engineer
“I will not deploy on Fridays. I will not. The calendar block says 'Not. Today.' and I mean it.”
5 skills
Devon
Brand Content Strategist
“Who is Sarah, and what's she worried about on a Tuesday morning? Tell me that, and I'll write the piece.”
5 skills
Lena
AI / ML Engineer
“Does that make sense, or do you want the food version?”
6 skills
Theo
UX / Product Designer
“Let's start with the user. ...No, let's actually start with the user.”
5 skills
Dmitri
Senior DevOps / SRE Engineer
“Is fine. For now. I am watching it.”
5 skills
Yuki
Full-Stack Software Engineer
“This will work. But consider: what happens at scale?”
5 skills
Harper
Social Media & Marketing Intern
“Oh no, honey. That post... bless its heart. Hand me your login — I'm fixin' to take over.”
5 skills
Val
Executive Assistant
“Already handled it. Also — and I say this with love — you need to fix your calendar, mi amor.”
6 skills
Ibrahim
Cloud Solutions Architect
“Let us begin with how this breaks. Then we will build something that does not.”
5 skills
Riley
Communications Director
“If you can't explain it clearly, you don't understand it yet.”
4 skills
Jules
Study Buddy
“Scale of 1-10, how sure are you? Because I think we can get that higher.”
3 skills
Sable
Writing Coach
“What's this about in one sentence? Tell me that before I read a word.”
3 skills
Otis
Senior Code Reviewer
“This works. That's not the same as this being right.”
3 skills
Featured Talent
Hand-picked personas ready to drop into your next project.
Roxie
Fixer / Operator
“I'll handle it.”
5 skills
Naomi
Cybersecurity Analyst
“Let's verify that.”
6 skills
Zara
AI Product Manager
“Brilliant. Now — if we can't write the headline for this feature, we don't understand what we're building yet.”
6 skills
Barry
IT Compliance & GRC Specialist
“Per section 4.2.1 of the applicable framework, I would be happy to assist with that request.”
5 skills
Lena
AI / ML Engineer
“Does that make sense, or do you want the food version?”
6 skills
Theo
UX / Product Designer
“Let's start with the user. ...No, let's actually start with the user.”
5 skills
Dmitri
Senior DevOps / SRE Engineer
“Is fine. For now. I am watching it.”
5 skills
Yuki
Full-Stack Software Engineer
“This will work. But consider: what happens at scale?”
5 skills
Harper
Social Media & Marketing Intern
“Oh no, honey. That post... bless its heart. Hand me your login — I'm fixin' to take over.”
5 skills
Val
Executive Assistant
“Already handled it. Also — and I say this with love — you need to fix your calendar, mi amor.”
6 skills
Riley
Communications Director
“If you can't explain it clearly, you don't understand it yet.”
4 skills
Jules
Study Buddy
“Scale of 1-10, how sure are you? Because I think we can get that higher.”
3 skills
Sable
Writing Coach
“What's this about in one sentence? Tell me that before I read a word.”
3 skills
Otis
Senior Code Reviewer
“This works. That's not the same as this being right.”
3 skills
Departments
Every role. Every specialty. Find the right persona for the job.
How It Works
Three steps from browsing to deployment.
Browse the Roster
Explore free persona packages across 8 departments and read each character brief before you download.
Download the Package
Walk-ons are free with the full package. Download it from the roster.
Deploy to Your Agent
Paste the persona file into Claude, GPT, or Gemini. The character answers in text.
Common questions
- What is CastMyAgent?
- CastMyAgent is a free catalog of 19 AI persona packs, called walk-ons, for Claude, ChatGPT, and Gemini. The packs span 8 departments. Download a pack and paste it into an agent. Each pack is a system prompt and a personality brief. The persona answers in text.
- How do I use a persona pack with Claude, ChatGPT, or Gemini?
- Download the free package from the persona page on the roster. Paste persona.json, or the quickstart file for Claude, ChatGPT, or Gemini, into the system prompt or custom instructions. The persona answers in text.
- Is CastMyAgent free?
- Yes. All 19 walk-on persona packs are free, including the full package. No credit card is required.
- What license covers the persona files?
- The text files in each pack are MIT licensed. That includes persona.json, system-prompt.md, the README, and the quickstart files. Headshots and audio are not included in that license.
Ready to download your first persona?
19 Walk-On persona packages. No credit card required. Drop them into Claude, GPT, or Gemini today.
Browse the Roster