How to use
- Copy the installation command and review the source package before installing it in your own agent environment.
- Check the source document for required tools, credentials and supported hosts.
- Describe your input and desired deliverable; review the output against the source material.
npx skills add https://github.com/gillesdandrea/gda-skills --skill zodBefore you start
- Installation does not include a model subscription, API allowance or permission to access your files.
- Repository stars and installation counts describe activity, not an independent quality or security test.
Original skill document
Rendered from the source repository. Headings, examples, code, tables, links, and referenced images are preserved.
Zod 4.5
Training data skews Zod 3, and even Zod 4 knowledge usually stops at 4.0. The installed version is in package.json. Each row below names the minor that introduced it, so skip rows above the installed version.
Write the v4 idiom
| Instead of (v3 habit) | Write (v4) |
|---|---|
z.string().email() / .uuid() / .url() | z.email(), z.uuid(), z.url(), z.hex(), z.hash("sha256"), z.creditCard() — top-level |
z.string().datetime() | z.iso.datetime() (also z.iso.date(), z.iso.time(), z.iso.duration()) |
message: / invalid_type_error / required_error / errorMap | one error: param — a string or (issue) => string |
.strict() / .passthrough() | z.strictObject({...}) / z.looseObject({...}) |
.merge(other) | .extend({...}); .safeExtend({...}) when the base has refinements |
.deepPartial() method | z.deepPartial(schema) (4.5) |
paired one-way .transform()s | z.codec(inSchema, outSchema, { decode, encode }) → .decode() / .encode() / .safeDecode() |
regex .refine() for a named format | z.stringFormat("name", fnOrRegex) |
.optional() when the key may be absent but never undefined | .exactOptional() (4.3); .exactPartial() for whole objects (4.5) |
z.union where exactly one branch must match | z.xor([...]) (4.2) |
| hand-written JSON Schema | z.toJSONSchema(schema) / z.fromJSONSchema(json) (4.2) |
z.lazy(() => Node) for a recursive object | a getter on the object: get children() { return z.array(Node); } |
Added after 4.0
- 4.1 codecs (
z.codec,z.decode,z.encode),.safeExtend(),z.hash(),z.hex(). - 4.2
z.fromJSONSchema(),z.xor(),z.looseRecord(keySchema, valueSchema)— record that tolerates keys outside the key schema. - 4.3
.exactOptional(),.apply(fn)for reusable check bundles,.with(...checks)alias of.check(),.brand<"Name", "in" | "out" | "inout">(), type-predicate.refine((s): s is "a" => ...)narrowing the output type,z.string().slugify(),z.map().min/max/nonempty(). - 4.4
z.invertCodec(codec),.superRefine({ when, ... })conditional refinement,ctx.addIssue()inside.transform(). - 4.5
z.compile(schema)(3–9x faster parse; orimport "zod/compile"at the entry point to compile everything),z.validate(schema, input): booleanfor a cheap validity check,z.properties({...})multi-property check forz.instanceof,z.input(schema)/z.output(schema)to parse against one side of a codec,z.toZod<T>()(schema)to assert a schema matches a static type,z.getDiscriminatedOption(union, value).
Facts that bite
- Error precedence is reversed from v3: a schema-level
errorwins over one passed to.parse(data, { error }). - Refined objects are locked:
.pick(),.omit(),.extend()(overwriting keys) and.merge()throw on a schema carrying refinements. Reach for.safeExtend(), or refine last. - `z.iso.datetime()` requires seconds since 4.5 (RFC 3339);
"2024-01-01T00:00Z"fails. - String `.min()/.max()/.length()` count code points since 4.5, not UTF-16 units. Emoji count as one.
- `z.object({ v: z.undefined() })` requires the key since 4.4; use
.optional()for "may be absent". - Issue types live under
z.core.$ZodIssue*; enum and literal mismatches merge into$ZodIssueInvalidValue;$ZodIssueInvalidKeyand$ZodIssueInvalidElementcover record, map and set failures. - Unchanged and still expected:
z.inferfor types,safeParseat boundaries, discriminated unions, getters for recursive objects.
API detail beyond this page: Context7, library ID /websites/zod_dev.
