Language Examples

ERA Agent supports multiple programming languages. Each language runs in an isolated VM with its own runtime environment. This guide provides examples for each supported language.

Using REST Clients (Postman, Insomnia, Restfox)

When copying JSON examples to paste into REST clients, look for the “JSON Body” sections below each curl example. These provide single-line JSON that’s ready to paste.

Important: Make sure newlines appear as \n (two characters: backslash + n) in your REST client, not as actual line breaks. If you’re getting JSON parse errors about “control characters,” check that \n isn’t being converted to actual newlines.

Example that works in REST clients:

{"language":"go","code":"package main\nimport \"fmt\"\nfunc main() { fmt.Println(\"Hello from Go!\") }"}

Python

Python 3.x with the standard library.

One-Shot Execution

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"python","code":"print(\"Hello from Python!\")\nprint(2 + 2)"}'

JSON Body:

{"language":"python","code":"print(\"Hello from Python!\")\nprint(2 + 2)"}

Output:

Hello from Python!
4

Math and Standard Library

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"python","code":"import math\nprint(f\"Pi: {math.pi}\")\nprint(f\"Sqrt(16): {math.sqrt(16)}\")"}'

JSON Body:

{"language":"python","code":"import math\nprint(f\"Pi: {math.pi}\")\nprint(f\"Sqrt(16): {math.sqrt(16)}\")"}

Output:

Pi: 3.141592653589793
Sqrt(16): 4.0

Session-Based Execution

Create session:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions \
  -H "Content-Type: application/json" \
  -d '{"language":"python","persistent":true,"session_id":"python-workspace"}'

JSON Body:

{"language":"python","persistent":true,"session_id":"python-workspace"}

Initialize variables:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/python-workspace/run \
  -H "Content-Type: application/json" \
  -d '{"code":"counter = 0\nprint(f\"Counter initialized: {counter}\")"}'

JSON Body:

{"code":"counter = 0\nprint(f\"Counter initialized: {counter}\")"}

Variables persist:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/python-workspace/run \
  -H "Content-Type: application/json" \
  -d '{"code":"counter += 1\nprint(f\"Counter value: {counter}\")"}'

JSON Body:

{"code":"counter += 1\nprint(f\"Counter value: {counter}\")"}

Clean up:

curl -X DELETE https://era-agent.yawnxyz.workers.dev/api/sessions/python-workspace

Outputs:

Counter initialized: 0
Counter value: 1

File Operations

Create session:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions \
  -H "Content-Type: application/json" \
  -d '{"language":"python","persistent":true,"session_id":"python-files"}'

JSON Body:

{"language":"python","persistent":true,"session_id":"python-files"}

Write file:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/python-files/run \
  -H "Content-Type: application/json" \
  -d '{"code":"with open(\"data.txt\", \"w\") as f:\n    f.write(\"Line 1\\nLine 2\\nLine 3\")\nprint(\"File created!\")"}'

JSON Body:

{"code":"with open(\"data.txt\", \"w\") as f:\n    f.write(\"Line 1\\nLine 2\\nLine 3\")\nprint(\"File created!\")"}

Read file:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/python-files/run \
  -H "Content-Type: application/json" \
  -d '{"code":"with open(\"data.txt\", \"r\") as f:\n    content = f.read()\nprint(f\"File contents:\\n{content}\")"}'

JSON Body:

{"code":"with open(\"data.txt\", \"r\") as f:\n    content = f.read()\nprint(f\"File contents:\\n{content}\")"}

Node.js

JavaScript runtime with Node.js APIs.

One-Shot Execution

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"node","code":"console.log(\"Hello from Node.js!\"); console.log(Math.PI);"}'

JSON Body:

{"language":"node","code":"console.log(\"Hello from Node.js!\"); console.log(Math.PI);"}

Output:

Hello from Node.js!
3.141592653589793

Math and Built-ins

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"node","code":"console.log(\"Pi:\", Math.PI);\nconsole.log(\"Sqrt(16):\", Math.sqrt(16));\nconsole.log(\"Random:\", Math.random());"}'

JSON Body:

{"language":"node","code":"console.log(\"Pi:\", Math.PI);\nconsole.log(\"Sqrt(16):\", Math.sqrt(16));\nconsole.log(\"Random:\", Math.random());"}

Output:

Pi: 3.141592653589793
Sqrt(16): 4
Random: 0.123456789

Session-Based Execution

Create session:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions \
  -H "Content-Type: application/json" \
  -d '{"language":"node","persistent":true,"session_id":"node-workspace"}'

JSON Body:

{"language":"node","persistent":true,"session_id":"node-workspace"}

Initialize variables:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/node-workspace/run \
  -H "Content-Type: application/json" \
  -d '{"code":"let counter = 0;\nconsole.log(`Counter initialized: ${counter}`);"}'

JSON Body:

{"code":"let counter = 0;\nconsole.log(`Counter initialized: ${counter}`);"}

Variables persist:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/node-workspace/run \
  -H "Content-Type: application/json" \
  -d '{"code":"counter += 1;\nconsole.log(`Counter value: ${counter}`);"}'

JSON Body:

{"code":"counter += 1;\nconsole.log(`Counter value: ${counter}`);"}

Outputs:

Counter initialized: 0
Counter value: 1

Working with JSON

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"node","code":"const data = { name: \"ERA Agent\", version: \"1.0\" };\nconsole.log(\"JSON:\", JSON.stringify(data, null, 2));"}'

JSON Body:

{"language":"node","code":"const data = { name: \"ERA Agent\", version: \"1.0\" };\nconsole.log(\"JSON:\", JSON.stringify(data, null, 2));"}

TypeScript

TypeScript with automatic transpilation using tsx.

One-Shot Execution

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"typescript","code":"const message: string = \"Hello from TypeScript!\";\nconsole.log(message);\nconst sum: number = 2 + 2;\nconsole.log(sum);"}'

JSON Body:

{"language":"typescript","code":"const message: string = \"Hello from TypeScript!\";\nconsole.log(message);\nconst sum: number = 2 + 2;\nconsole.log(sum);"}

Output:

Hello from TypeScript!
4

Type-Safe Math

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"typescript","code":"const pi: number = Math.PI;\nconst sqrt: number = Math.sqrt(16);\nconsole.log(`Pi: ${pi}`);\nconsole.log(`Sqrt(16): ${sqrt}`);"}'

JSON Body:

{"language":"typescript","code":"const pi: number = Math.PI;\nconst sqrt: number = Math.sqrt(16);\nconsole.log(`Pi: ${pi}`);\nconsole.log(`Sqrt(16): ${sqrt}`);"}

Output:

Pi: 3.141592653589793
Sqrt(16): 4

Session-Based Execution

Create session:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions \
  -H "Content-Type: application/json" \
  -d '{"language":"typescript","persistent":true,"session_id":"typescript-workspace"}'

JSON Body:

{"language":"typescript","persistent":true,"session_id":"typescript-workspace"}

Initialize with types:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/typescript-workspace/run \
  -H "Content-Type: application/json" \
  -d '{"code":"let counter: number = 0;\nconsole.log(`Counter initialized: ${counter}`);"}'

JSON Body:

{"code":"let counter: number = 0;\nconsole.log(`Counter initialized: ${counter}`);"}

Type-safe operations:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/typescript-workspace/run \
  -H "Content-Type: application/json" \
  -d '{"code":"counter += 1;\nconsole.log(`Counter value: ${counter}`);"}'

JSON Body:

{"code":"counter += 1;\nconsole.log(`Counter value: ${counter}`);"}

Outputs:

Counter initialized: 0
Counter value: 1

Interfaces and Types

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"typescript","code":"interface User { name: string; age: number; }\nconst user: User = { name: \"Alice\", age: 30 };\nconsole.log(`User: ${user.name}, Age: ${user.age}`);"}'

JSON Body:

{"language":"typescript","code":"interface User { name: string; age: number; }\nconst user: User = { name: \"Alice\", age: 30 };\nconsole.log(`User: ${user.name}, Age: ${user.age}`);"}

Go

Go 1.21+ with the standard library.

One-Shot Execution

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"go","code":"package main\nimport \"fmt\"\nfunc main() { fmt.Println(\"Hello from Go!\") }"}'

JSON Body:

{"language":"go","code":"package main\nimport \"fmt\"\nfunc main() { fmt.Println(\"Hello from Go!\") }"}

Output:

Hello from Go!

Math and Standard Library

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"go","code":"package main\nimport (\n\t\"fmt\"\n\t\"math\"\n)\nfunc main() {\n\tfmt.Println(\"Pi:\", math.Pi)\n\tfmt.Println(\"Sqrt(16):\", math.Sqrt(16))\n}"}'

JSON Body:

{"language":"go","code":"package main\nimport (\n\t\"fmt\"\n\t\"math\"\n)\nfunc main() {\n\tfmt.Println(\"Pi:\", math.Pi)\n\tfmt.Println(\"Sqrt(16):\", math.Sqrt(16))\n}"}

Output:

Pi: 3.141592653589793
Sqrt(16): 4

Session-Based Execution

Create session:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions \
  -H "Content-Type: application/json" \
  -d '{"language":"go","persistent":true,"session_id":"go-workspace"}'

JSON Body:

{"language":"go","persistent":true,"session_id":"go-workspace"}

Run Go code:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/go-workspace/run \
  -H "Content-Type: application/json" \
  -d '{"code":"package main\nimport \"fmt\"\nfunc main() { fmt.Println(\"Running in Go session!\") }"}'

JSON Body:

{"code":"package main\nimport \"fmt\"\nfunc main() { fmt.Println(\"Running in Go session!\") }"}

Math example:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/go-workspace/run \
  -H "Content-Type: application/json" \
  -d '{"code":"package main\nimport (\n\t\"fmt\"\n\t\"math\"\n)\nfunc main() {\n\tfmt.Println(\"Pi:\", math.Pi)\n\tfmt.Println(\"Sqrt(16):\", math.Sqrt(16))\n}"}'

JSON Body:

{"code":"package main\nimport (\n\t\"fmt\"\n\t\"math\"\n)\nfunc main() {\n\tfmt.Println(\"Pi:\", math.Pi)\n\tfmt.Println(\"Sqrt(16):\", math.Sqrt(16))\n}"}

Outputs:

Running in Go session!
Pi: 3.141592653589793
Sqrt(16): 4

Structs and Functions

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"go","code":"package main\nimport \"fmt\"\ntype User struct {\n\tName string\n\tAge  int\n}\nfunc main() {\n\tuser := User{Name: \"Alice\", Age: 30}\n\tfmt.Printf(\"User: %s, Age: %d\\n\", user.Name, user.Age)\n}"}'

JSON Body:

{"language":"go","code":"package main\nimport \"fmt\"\ntype User struct {\n\tName string\n\tAge  int\n}\nfunc main() {\n\tuser := User{Name: \"Alice\", Age: 30}\n\tfmt.Printf(\"User: %s, Age: %d\\n\", user.Name, user.Age)\n}"}

File Operations

Create session:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions \
  -H "Content-Type: application/json" \
  -d '{"language":"go","persistent":true,"session_id":"go-files"}'

JSON Body:

{"language":"go","persistent":true,"session_id":"go-files"}

Write file:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/go-files/run \
  -H "Content-Type: application/json" \
  -d '{"code":"package main\nimport (\n\t\"fmt\"\n\t\"os\"\n)\nfunc main() {\n\terr := os.WriteFile(\"data.txt\", []byte(\"Hello from Go!\"), 0644)\n\tif err != nil {\n\t\tfmt.Println(\"Error:\", err)\n\t\treturn\n\t}\n\tfmt.Println(\"File created!\")\n}"}'

JSON Body:

{"code":"package main\nimport (\n\t\"fmt\"\n\t\"os\"\n)\nfunc main() {\n\terr := os.WriteFile(\"data.txt\", []byte(\"Hello from Go!\"), 0644)\n\tif err != nil {\n\t\tfmt.Println(\"Error:\", err)\n\t\treturn\n\t}\n\tfmt.Println(\"File created!\")\n}"}

Read file:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/go-files/run \
  -H "Content-Type: application/json" \
  -d '{"code":"package main\nimport (\n\t\"fmt\"\n\t\"os\"\n)\nfunc main() {\n\tdata, err := os.ReadFile(\"data.txt\")\n\tif err != nil {\n\t\tfmt.Println(\"Error:\", err)\n\t\treturn\n\t}\n\tfmt.Printf(\"File contents: %s\\n\", data)\n}"}'

JSON Body:

{"code":"package main\nimport (\n\t\"fmt\"\n\t\"os\"\n)\nfunc main() {\n\tdata, err := os.ReadFile(\"data.txt\")\n\tif err != nil {\n\t\tfmt.Println(\"Error:\", err)\n\t\treturn\n\t}\n\tfmt.Printf(\"File contents: %s\\n\", data)\n}"}

Deno

Deno 1.40+ with native TypeScript and JavaScript support.

One-Shot Execution

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"deno","code":"console.log(\"Hello from Deno!\");\nconsole.log(\"Deno version:\", Deno.version.deno);"}'

JSON Body:

{"language":"deno","code":"console.log(\"Hello from Deno!\");\nconsole.log(\"Deno version:\", Deno.version.deno);"}

Output:

Hello from Deno!
Deno version: 1.40.0

TypeScript Support

Deno runs TypeScript natively without any transpilation step:

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"deno","code":"const message: string = \"Hello from Deno TypeScript!\";\nconst num: number = 42;\nconsole.log(`${message} The answer is ${num}`);"}'

JSON Body:

{"language":"deno","code":"const message: string = \"Hello from Deno TypeScript!\";\nconst num: number = 42;\nconsole.log(`${message} The answer is ${num}`);"}

Output:

Hello from Deno TypeScript! The answer is 42

Session-Based Execution

Create session:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions \
  -H "Content-Type: application/json" \
  -d '{"language":"deno","persistent":true,"session_id":"deno-workspace"}'

JSON Body:

{"language":"deno","persistent":true,"session_id":"deno-workspace"}

Run Deno code:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/deno-workspace/run \
  -H "Content-Type: application/json" \
  -d '{"code":"console.log(\"Running in Deno session!\");\nconsole.log(\"Runtime:\", Deno.version.deno);"}'

JSON Body:

{"code":"console.log(\"Running in Deno session!\");\nconsole.log(\"Runtime:\", Deno.version.deno);"}

TypeScript in session:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/deno-workspace/run \
  -H "Content-Type: application/json" \
  -d '{"code":"interface User {\n  name: string;\n  age: number;\n}\nconst user: User = { name: \"Alice\", age: 30 };\nconsole.log(`User: ${user.name}, Age: ${user.age}`);"}'

JSON Body:

{"code":"interface User {\n  name: string;\n  age: number;\n}\nconst user: User = { name: \"Alice\", age: 30 };\nconsole.log(`User: ${user.name}, Age: ${user.age}`);"}

Outputs:

Running in Deno session!
Runtime: 1.40.0
User: Alice, Age: 30

Standard Library

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"deno","code":"console.log(\"Pi:\", Math.PI);\nconsole.log(\"Sqrt(16):\", Math.sqrt(16));\nconsole.log(\"Random:\", Math.random());"}'

JSON Body:

{"language":"deno","code":"console.log(\"Pi:\", Math.PI);\nconsole.log(\"Sqrt(16):\", Math.sqrt(16));\nconsole.log(\"Random:\", Math.random());"}

Output:

Pi: 3.141592653589793
Sqrt(16): 4
Random: 0.123456789

File Operations

Create session:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions \
  -H "Content-Type: application/json" \
  -d '{"language":"deno","persistent":true,"session_id":"deno-files"}'

JSON Body:

{"language":"deno","persistent":true,"session_id":"deno-files"}

Write file:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/deno-files/run \
  -H "Content-Type: application/json" \
  -d '{"code":"const encoder = new TextEncoder();\nconst data = encoder.encode(\"Hello from Deno!\");\nDeno.writeFileSync(\"data.txt\", data);\nconsole.log(\"File created!\");"}'

JSON Body:

{"code":"const encoder = new TextEncoder();\nconst data = encoder.encode(\"Hello from Deno!\");\nDeno.writeFileSync(\"data.txt\", data);\nconsole.log(\"File created!\");"}

Read file:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/deno-files/run \
  -H "Content-Type: application/json" \
  -d '{"code":"const decoder = new TextDecoder();\nconst data = Deno.readFileSync(\"data.txt\");\nconst text = decoder.decode(data);\nconsole.log(\"File contents:\", text);"}'

JSON Body:

{"code":"const decoder = new TextDecoder();\nconst data = Deno.readFileSync(\"data.txt\");\nconst text = decoder.decode(data);\nconsole.log(\"File contents:\", text);"}

Working with JSON

curl:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/execute \
  -H "Content-Type: application/json" \
  -d '{"language":"deno","code":"const data = { name: \"ERA Agent\", runtime: \"Deno\", version: Deno.version.deno };\nconsole.log(JSON.stringify(data, null, 2));"}'

JSON Body:

{"language":"deno","code":"const data = { name: \"ERA Agent\", runtime: \"Deno\", version: Deno.version.deno };\nconsole.log(JSON.stringify(data, null, 2));"}

Language Comparison

Feature	Python	Node.js	TypeScript	Go	Deno
Runtime	Python 3.x	Node.js	tsx	Go 1.21+	Deno 1.40+
Typing	Dynamic	Dynamic	Static	Static	Static/Dynamic
Execution	Interpreter	Interpreter	Transpiled	Compiled	Native TS/JS
Speed	Medium	Fast	Fast	Very Fast	Fast
Use Cases	Data analysis, scripting	APIs, async tasks	Type-safe Node.js	Systems, performance	Modern TS/JS, secure by default

Best Practices

Choosing a Language

• Python: Data processing, scientific computing, general scripting
• Node.js: Async operations, JSON processing, web scraping
• TypeScript: Type-safe applications, large codebases
• Go: Performance-critical code, concurrent operations
• Deno: Modern TypeScript/JavaScript with native support, secure by default

Code Organization

For complex code, use sessions with multiple runs:

Setup phase:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/my-app/run \
  -H "Content-Type: application/json" \
  -d '{"code":"# Import libraries and initialize"}'

JSON Body:

{"code":"# Import libraries and initialize"}

Processing phase:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/my-app/run \
  -H "Content-Type: application/json" \
  -d '{"code":"# Process data using initialized state"}'

JSON Body:

{"code":"# Process data using initialized state"}

Output phase:

curl -X POST https://era-agent.yawnxyz.workers.dev/api/sessions/my-app/run \
  -H "Content-Type: application/json" \
  -d '{"code":"# Generate and save results"}'

JSON Body:

{"code":"# Generate and save results"}

Error Handling

All languages support standard error handling:

Python:

try:
    result = risky_operation()
except Exception as e:
    print(f"Error: {e}")

Node.js:

try {
    const result = riskyOperation();
} catch (error) {
    console.log(`Error: ${error.message}`);
}

TypeScript:

try {
    const result: number = riskyOperation();
} catch (error) {
    console.log(`Error: ${error}`);
}

Go:

result, err := riskyOperation()
if err != nil {
    fmt.Printf("Error: %v\n", err)
    return
}

Quick Reference

Python example:

{"language":"python","code":"print('Hello World')"}

Node.js example:

{"language":"node","code":"console.log('Hello World');"}

TypeScript example:

{"language":"typescript","code":"const msg: string = 'Hello World';\nconsole.log(msg);"}

Go example:

{"language":"go","code":"package main\nimport \"fmt\"\nfunc main() { fmt.Println(\"Hello World\") }"}

Deno example:

{"language":"deno","code":"console.log('Hello World from Deno!');"}

Next Steps

• Session Management - Working with persistent sessions
• File Operations - Managing files in sessions
• API Reference - Complete API documentation