Flutter Implement JSON Serialization

What it does

When your agent uses it

• Manually mapping JSON keys to class properties for simple data structures
• Tasks that involve Cross-platform mobile apps

Example prompts

• “/flutter-implement-json-serialization”

Workflow steps

4 steps, taken from the first numbered list in SKILL.md.

1. 1Define the Model: Create a class with properties matching the JSON keys.
2. 2Implement fromJson: Extract values from the Map and cast them to the appropriate Dart types. Use pattern matching or explicit casting.
3. 3Implement toJson: Return a Map mapping the class properties back to their JSON string keys.
4. 4Validate: Execute unit tests to ensure type safety, autocompletion, and compile-time exception handling function correctly.

What it can do on your machine

Read from SKILL.md and the folder at commit 9ff3f94. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  No scripts in the folder and no shell commands in SKILL.md (its code samples are dart).

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Flutter Implement JSON Serialization loads about 1.4k tokens when it runs. Until then it costs about 50 tokens; SKILL.md has 407 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~50

When it runs · the whole SKILL.md, loaded when a task matches

~1.4k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from abdulmominsakib/localmind at commit 9ff3f94, republished under its MIT licence (© abdulmominsakib). 407 words, ~1,413 tokens.

name

flutter-implement-json-serialization

description

Create model classes with `fromJson` and `toJson` methods using `dart:convert`. Use when manually mapping JSON keys to class properties for simple data structures.

metadata.model

models/gemini-3.1-pro-preview

metadata.last_modified

Tue, 21 Apr 2026 21:44:50 GMT

import 'dart:convert';

class User {
  final int id;
  final String name;
  final String email;

  const User({
    required this.id,
    required this.name,
    required this.email,
  });

  // Factory constructor for deserialization
  factory User.fromJson(Map<String, dynamic> json) {
    return switch (json) {
      {
        'id': int id,
        'name': String name,
        'email': String email,
      } => 
        User(
          id: id,
          name: name,
          email: email,
        ),
      _ => throw const FormatException('Failed to load User.'),
    };
  }

  // Method for serialization
  Map<String, dynamic> toJson() {
    return {
      'id': id,
      'name': name,
      'email': email,
    };
  }
}

import 'dart:convert';
import 'package:http/http.dart' as http;

Future<User> fetchUser(http.Client client, int userId) async {
  final response = await client.get(
    Uri.parse('https://api.example.com/users/$userId'),
    headers: {'Accept': 'application/json'},
  );

  if (response.statusCode == 200) {
    // Decode returns dynamic, cast to Map<String, dynamic>
    final Map<String, dynamic> jsonMap = jsonDecode(response.body) as Map<String, dynamic>;
    return User.fromJson(jsonMap);
  } else {
    throw Exception('Failed to load user');
  }
}

import 'dart:convert';
import 'package:flutter/foundation.dart';
import 'package:http/http.dart' as http;

// Top-level function required for compute()
List<User> parseUsers(String responseBody) {
  final parsed = (jsonDecode(responseBody) as List<dynamic>).cast<Map<String, dynamic>>();
  return parsed.map<User>((json) => User.fromJson(json)).toList();
}

Future<List<User>> fetchUsers(http.Client client) async {
  final response = await client.get(
    Uri.parse('https://api.example.com/users'),
    headers: {'Accept': 'application/json'},
  );

  if (response.statusCode == 200) {
    // Offload expensive parsing to a background isolate
    return compute(parseUsers, response.body);
  } else {
    throw Exception('Failed to load users');
  }
}

© abdulmominsakib, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

Just SKILL.md in .agents/skills/flutter-implement-json-serialization of abdulmominsakib/localmind.

Open the folder on GitHubat commit 9ff3f94

Used in 1 other repository

We found 1 copy of this SKILL.md (exact, near-identical or edited) in other folders, from 1 other GitHub owner. This page covers the copy in abdulmominsakib/localmind, which our catalogue first saw on October 7, 2026.

• aiskillstore/marketplaceskills/flutter/flutter-implement-json-serialization