Data models

The tables below describe the public JSON contract. Fields that are not documented here are not part of that contract and clients must not depend on them.

User creation request

Field	Type	Required	Nullable	Constraints
username	string	Yes	No	2–32 ASCII lowercase letters, digits, _, or .; no consecutive periods
display_name	string	No	Yes	2–32 Unicode characters; no leading or trailing whitespace; not blank
password	string	Yes	No	8–128 Unicode characters; at least one lowercase, uppercase, digit, and punctuation or symbol character

Unknown JSON properties are currently ignored. Clients should not send them or depend on that behavior remaining part of the contract.

Login request

Field	Type	Required	Nullable	Constraints
username	string	Yes	No	Same lowercase username grammar as account creation
password	string	Yes	No	Non-empty; at most 128 Unicode characters

User

Field	Type	Always present	Nullable	Meaning
id	decimal string	Yes	No	User Sonyflake ID
username	string	Yes	No	Exact lowercase username
display_name	string	Yes	Yes	Optional public display name
created_at	RFC 3339 string	Yes	No	Account creation time
updated_at	RFC 3339 string	Yes	No	Last account update time; no update operation is currently public

Passwords are never returned by the API.

Authentication session

The login response represents a newly created authentication session:

Field	Type	Always present	Nullable	Meaning
id	decimal string	Yes	No	Session Sonyflake ID
token	string	Yes	No	43-character opaque bearer token returned once
token_type	string	Yes	No	Always Bearer
user	User	Yes	No	Account authenticated by the session
created_at	RFC 3339 string	Yes	No	Session creation time
expires_at	RFC 3339 string	Yes	No	Time after which the token is rejected

The raw token appears only in the login response and cannot be retrieved later.

Link creation request

Field	Type	Required	Nullable	Constraints
url	string	Yes	No	Absolute HTTP(S) URL; hostname required; no user information; maximum 4096 UTF-8 bytes

Link

Field	Type	Always present	Nullable	Meaning
id	decimal string	Yes	No	Link Sonyflake ID
user_id	decimal string	Yes	No	Owning user’s Sonyflake ID
code	string	Yes	No	Eight case-sensitive Base62 characters
target_url	URI string	Yes	No	Stored redirect destination
short_url	URI string	Yes	No	Absolute public URL for the short code
created_at	RFC 3339 string	Yes	No	Link creation time

Link collection

GET /api/v1/links returns an object with one always-present links array. The array contains zero to 50 Link objects and is never null.

Error

Every JSON failure wraps one error body in an errors property:

Field	Type	Always present	Meaning
errors.code	string	Yes	Stable machine-readable code
errors.message	string	No	Request-level explanation
errors.fields	object of strings	No	Field names mapped to validation explanations

See Errors for all public codes and examples.