Parallel tool execution in Agentic AI

Introduction

Parallel tool execution helps run many tasks at the same time. This saves time and makes work faster.

When you want to ask multiple tools questions at once.

When you need to get answers from different sources quickly.

When you want to speed up a process by doing many steps together.

When you have many small jobs that can run without waiting for each other.

When you want to improve efficiency in AI workflows by multitasking.

Syntax

Agentic AI

results = agent_executor.invoke_parallel([tool1, tool2, tool3], inputs_list)

agent_executor.invoke_parallel runs tools at the same time.

inputs_list is a list of inputs matching each tool.

Examples

This runs a search and a calculator tool at the same time with different inputs.

Agentic AI

results = agent_executor.invoke_parallel([search_tool, calculator], ["weather today", "2+2"])

This runs translation and summarization tools in parallel.

Agentic AI

results = agent_executor.invoke_parallel([translator, summarizer], ["Hello", "Long article text"])

Sample Model

This code defines two simple tools as functions. It runs them at the same time using threads. Then it prints each tool's result.

Agentic AI

from concurrent.futures import ThreadPoolExecutor

# Define two simple tools as functions
def tool1(input_text):
    return f"Tool1 processed: {input_text}"

def tool2(input_text):
    return f"Tool2 processed: {input_text}"

# Function to run tools in parallel
def run_tools_parallel(tools, inputs):
    with ThreadPoolExecutor() as executor:
        futures = [executor.submit(tool, inp) for tool, inp in zip(tools, inputs)]
        results = [future.result() for future in futures]
    return results

# Tools list and inputs
tools = [tool1, tool2]
inputs = ["data A", "data B"]

# Run tools in parallel
outputs = run_tools_parallel(tools, inputs)

# Print results
for output in outputs:
    print(output)

Important Notes

Parallel execution can speed up tasks but needs careful input-output matching.

Not all tools can run safely in parallel if they share resources.

Summary

Parallel tool execution runs many tools at once to save time.

Use it when tasks do not depend on each other.

It improves efficiency in AI workflows by multitasking.

Practice

1.

What is the main benefit of parallel tool execution in AI workflows?

easy

A. It makes tools run slower but more accurately.

B. It runs tools one after another to avoid errors.

C. It only works if tasks depend on each other.

D. It runs multiple tools at the same time to save time.

Solution

1. Step 1: Understand parallel execution

   Parallel execution means running many tasks at once, not one by one.

2. Step 2: Identify the benefit in AI workflows

   Running tools simultaneously saves time and improves efficiency.

3. Final Answer:

   It runs multiple tools at the same time to save time. -> Option D

4. Quick Check:

   Parallel execution = run many tools at once [OK]

Hint: Parallel means many at once, so it saves time [OK]

Common Mistakes:

• Thinking parallel means slower execution
• Believing tasks must depend on each other
• Confusing parallel with sequential execution

2.

Which of the following is the correct way to start parallel execution of two tools toolA and toolB in Python using concurrent.futures?

import concurrent.futures

with concurrent.futures.ThreadPoolExecutor() as executor:
    # What goes here?

easy

A. executor.parallel(toolA, toolB)

B. executor.run(toolA, toolB)

C. executor.submit(toolA); executor.submit(toolB)

D. executor.execute(toolA & toolB)

Solution

1. Step 1: Recall ThreadPoolExecutor usage

   The method to run functions in parallel is submit() for each function.

2. Step 2: Check the options

   Only executor.submit(toolA); executor.submit(toolB) correctly submits both tools for parallel execution.

3. Final Answer:

   executor.submit(toolA); executor.submit(toolB) -> Option C

4. Quick Check:

   Use submit() to run functions in parallel [OK]

Hint: Use submit() for each tool to run in parallel [OK]

Common Mistakes:

• Using non-existent methods like run() or execute()
• Trying to pass multiple tools in one call
• Confusing parallel execution syntax

3.

Given the code below, what will be the output?

import concurrent.futures
import time

def tool1():
    time.sleep(2)
    return 'Done1'

def tool2():
    time.sleep(1)
    return 'Done2'

with concurrent.futures.ThreadPoolExecutor() as executor:
    future1 = executor.submit(tool1)
    future2 = executor.submit(tool2)
    print(future1.result())
    print(future2.result())

medium

A. Done2\nDone1

B. Done1\nDone2

C. Done1\nDone1

D. Done2\nDone2

Solution

1. Step 1: Understand parallel execution and sleep times

   tool1 sleeps 2 seconds, tool2 sleeps 1 second, both start together.

2. Step 2: Check order of result() calls

   future1.result() waits for tool1 (2s), then future2.result() waits for tool2 (1s). So output order matches calls, not completion time.

3. Final Answer:

   Done1 Done2 -> Option B

4. Quick Check:

   Results print in call order, not finish order [OK]

Hint: result() waits; output order matches calls, not finish time [OK]

Common Mistakes:

• Assuming output order matches task finish time
• Ignoring that result() blocks until done
• Confusing sleep durations with print order

4.

What is the error in the following code that tries to run two tools in parallel?

import concurrent.futures

def toolA():
    return 'A'

def toolB():
    return 'B'

with concurrent.futures.ThreadPoolExecutor() as executor:
    results = executor.map(toolA, toolB)
    print(list(results))

medium

A. executor.map expects a function and an iterable, but toolB is not iterable.

B. executor.map cannot run more than one function at a time.

C. Missing parentheses when calling toolA and toolB.

D. ThreadPoolExecutor cannot be used with map.

Solution

1. Step 1: Understand executor.map signature

   executor.map expects one function and an iterable of inputs to apply that function to.

2. Step 2: Identify the error in arguments

   Passing two functions (toolA, toolB) is wrong; toolB is not an iterable of inputs for toolA.

3. Final Answer:

   executor.map expects a function and an iterable, but toolB is not iterable. -> Option A

4. Quick Check:

   map(func, iterable) needs iterable inputs [OK]

Hint: map needs one function and iterable inputs, not two functions [OK]

Common Mistakes:

• Passing multiple functions to map
• Confusing map with submit
• Thinking map runs multiple different functions

5.

You want to run three independent AI tools toolX, toolY, and toolZ in parallel and collect their results as a dictionary with tool names as keys. Which code snippet correctly achieves this?

def toolX(): return 'X result'
def toolY(): return 'Y result'
def toolZ(): return 'Z result'

# Choose the correct parallel execution code

hard

A. import concurrent.futures
with concurrent.futures.ThreadPoolExecutor() as executor:
futures = {name: executor.submit(func) for name, func in {'toolX': toolX, 'toolY': toolY, 'toolZ': toolZ}.items()}
results = {name: future.result() for name, future in futures.items()}
print(results)

B. import concurrent.futures
with concurrent.futures.ThreadPoolExecutor() as executor:
results = executor.map(toolX, toolY, toolZ)
print(dict(results))

C. results = {}
for tool in [toolX, toolY, toolZ]:
results[tool.__name__] = tool()
print(results)

D. import threading
results = {}
def run_tool(name, func):
results[name] = func()
threads = []
for name, func in {'toolX': toolX, 'toolY': toolY, 'toolZ': toolZ}.items():
t = threading.Thread(target=run_tool, args=(name, func))
threads.append(t)
t.start()
for t in threads:
t.join()
print(results)

Solution

1. Step 1: Check parallel execution with ThreadPoolExecutor

   import concurrent.futures with concurrent.futures.ThreadPoolExecutor() as executor: futures = {name: executor.submit(func) for name, func in {'toolX': toolX, 'toolY': toolY, 'toolZ': toolZ}.items()} results = {name: future.result() for name, future in futures.items()} print(results) uses submit() for each tool, stores futures with names, then collects results correctly.

2. Step 2: Evaluate other options

   import concurrent.futures with concurrent.futures.ThreadPoolExecutor() as executor: results = executor.map(toolX, toolY, toolZ) print(dict(results)) misuses map with multiple functions; results = {} for tool in [toolX, toolY, toolZ]: results[tool.__name__] = tool() print(results) runs tools sequentially; import threading results = {} def run_tool(name, func): results[name] = func() threads = [] for name, func in {'toolX': toolX, 'toolY': toolY, 'toolZ': toolZ}.items(): t = threading.Thread(target=run_tool, args=(name, func)) threads.append(t) t.start() for t in threads: t.join() print(results) uses threading correctly but is more complex and not asked.

3. Final Answer:

   Option A correctly runs tools in parallel and collects results as a dictionary. -> Option A

4. Quick Check:

   submit() + dict comprehension collects parallel results [OK]

Hint: Use submit() with dict comprehension to map names to results [OK]

Common Mistakes:

• Using map() with multiple functions
• Running tools sequentially instead of parallel
• Confusing threading with ThreadPoolExecutor usage