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 skills add open-circle/agent-skills --skill valibotgit clone --depth 1 https://github.com/open-circle/agent-skillsWrote 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/open-circle/agent-skills/valibot)<a href="https://agentmods.dev/skills/open-circle/agent-skills/valibot"><img src="https://agentmods.dev/badge/skills/open-circle/agent-skills/valibot.svg" alt="Measured on agentmods" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector pass
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 5.1 | $0.00056 | $0.04687 |
| Opus 5 | $0.00028 | $0.02344 |
| Sonnet 5 | $0.00011 | $0.00937 |
| Haiku 4.5 | $0.00006 | $0.00469 |
Grade A, and why
valibot 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 8d 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 — 766 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Valibot
This skill helps you work effectively with Valibot, the modular and type-safe schema library for validating structural data.
When to use this skill
- When the user asks about schema validation with Valibot
- When creating or modifying Valibot schemas
- When parsing or validating user input
- When the user mentions Valibot, schema, or validation
- When migrating from Zod to Valibot
CRITICAL: Valibot vs Zod — Do Not Confuse!
Valibot and Zod have different APIs. Never mix them up!
Key Differences
| Feature | Zod ❌ | Valibot ✅ |
|---|---|---|
| Import | import { z } from 'zod' |
import * as v from 'valibot' |
| Validations | Chained methods: .email().min(5) |
Pipeline: v.pipe(v.string(), v.email(), v.minLength(5)) |
| Parsing | schema.parse(data) |
v.parse(schema, data) |
| Safe parsing | schema.safeParse(data) |
v.safeParse(schema, data) |
| Optional | z.string().optional() |
v.optional(v.string()) |
| Nullable | z.string().nullable() |
v.nullable(v.string()) |
| Default | z.string().default('x') |
v.optional(v.string(), 'x') |
| Transform | z.string().transform(fn) |
v.pipe(v.string(), v.transform(fn)) |
| Refine/Check | z.string().refine(fn) |
v.pipe(v.string(), v.check(fn)) |
| Enum | z.enum(['a', 'b']) |
v.picklist(['a', 'b']) |
| Native enum | z.nativeEnum(MyEnum) |
v.enum(MyEnum) |
| Union | z.union([a, b]) |
v.union([a, b]) |
| Discriminated union | z.discriminatedUnion('type', [...]) |
v.variant('type', [...]) |
| Intersection | z.intersection(a, b) |
v.intersect([a, b]) |
| Min/max length | .min(5).max(10) |
v.minLength(5), v.maxLength(10) |
| Min/max value | .gte(5).lte(10) |
v.minValue(5), v.maxValue(10) |
| Infer type | z.infer<typeof Schema> |
v.InferOutput<typeof Schema> |
| Infer input | z.input<typeof Schema> |
v.InferInput<typeof Schema> |
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.
- 8d ago First seen · 766 lines · 56 tokens per session scan A 8c7397be7b71
valibot is a skill published in the GitHub repository open-circle/agent-skills (15 stars, last pushed 17d ago), licensed MIT. It adds 56 tokens to every session and 4,687 once invoked, about $0.0003 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 2026-08-30.
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