Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/fattain-naime/engineering-docs/user-personas-behaviornpx skills add fattain-naime/engineering-docs --skill user-personas-behaviorgit clone --depth 1 https://github.com/fattain-naime/engineering-docsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/fattain-naime/engineering-docs/user-personas-behavior)<a href="https://agentmods.dev/skills/fattain-naime/engineering-docs/user-personas-behavior"><img src="https://agentmods.dev/badge/skills/fattain-naime/engineering-docs/user-personas-behavior.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00092 | $0.03156 |
| Opus 5 | $0.00046 | $0.01578 |
| Sonnet 5 | $0.00018 | $0.00631 |
| Haiku 4.5 | $0.00009 | $0.00316 |
Grade A, and why
user-personas-behavior scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 210 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Purpose
Produce a document that defines who a product or feature serves, what job they are trying to get done, what "success" concretely means for them and for the business, and what must be instrumented to measure it.
A persona is a tool for decisions, not a character sketch. "Priya, 34, marketing manager" tells an implementer nothing actionable. "A user who needs to approve or reject an expense report in under 60 seconds from a phone, several times a day" tells them exactly what to build and how to judge whether they succeeded.
Input
Works best with: The name of the product or feature. Also valuable: Any existing user research or support tickets, known user complaints, business goals this needs to serve, existing analytics setup.
Example invocation: Define user personas and success metrics for our team calendar-scheduling tool. Two clear user types so far: people trying to book a meeting fast, and people managing their own availability so they get booked less often outside working hours.
Key Concepts
Jobs-to-Be-Done (JTBD), Not Demographics
Define personas by the job they're hiring the product to do, not by age, gender, job title, or other demographic labels - those rarely change what gets built and can bake in assumptions that don't hold. Structure: "When [situation], I want to [motivation], so I can [expected outcome]."
Behavior Over Biography
Describe usage patterns that affect design decisions: frequency of use (daily vs. rare), context of use (mobile/on-the-go vs. desk), technical comfort with the domain (novice vs. power user), and tolerance for friction at this specific task. These directly inform UI and flow decisions; biographical detail generally doesn't.
Primary vs. Secondary Personas
Not every user matters equally to every decision. Name the primary persona(s) whose needs win in a trade-off, and secondary personas whose needs matter but yield when in conflict. Undeclared priority between personas causes design debates to stall indefinitely.
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 4d ago First seen · 210 lines · 92 tokens per session scan A e133ce438c77
user-personas-behavior is a skill published in the GitHub repository fattain-naime/engineering-docs (4 stars, last pushed 20d ago), licensed MIT. It adds 92 tokens to every session and 3,156 once invoked, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.
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