نظرة عامة على الحلقة الوكيلة
request، وفحص stop_reason، وتشغيل الأدوات، والتكرار
نظرة عامة على الحلقة الوكيلة درس مجاني في Claude Architect على CoddyKit. هذا هو الدرس 4 من أصل 4. يمكنك قراءة الدرس كاملاً أدناه مجاناً — ثم تمرن عليه مباشرة في المتصفح باستخدام محرر أكواد مدمج ومدرس ذكاء اصطناعي متاح 24/7. هذا الدرس جزء من مسار التعلم في Claude Architect، وتقدمك يتزامن عبر الويب وتطبيق CoddyKit. تتضمن دورة Claude Architect 4 دروس في المجموع.
بعض أجزاء هذا الدرس لم تُترجم بعد وتظهر باللغة الإنجليزية.
What Is the Agentic Loop?
An agent is just a loop around the Claude Messages API. You send a request, Claude either finishes or asks to run a tool, you run it, and you send the results back. Repeat until Claude is done.
The whole pattern is four steps:
- Request — call the API with your message history.
- Inspect the
stop_reasonin the response. - Run tools if Claude asked for them, then add the results to the history.
- Repeat until
stop_reasonisend_turn.
Master this one loop and you understand the core of every agent.
The Request: Full History Every Turn
The Claude API is stateless. The model keeps no memory between calls, so you must send the full message history every single turn.
A request carries these fields:
model— which Claude model to use.max_tokens— the output cap.system— the system prompt.messages— the entire conversation so far.tools— the tools Claude may call.
If you forget to append a turn, Claude simply won't know it happened.
import anthropic
client = anthropic.Anthropic()
response = client.messages.create(
model="claude-opus-4-8",
max_tokens=1024,
system="You are a helpful weather assistant.",
tools=tools,
messages=messages, # the FULL history, every turn
)The Response: Read stop_reason
Every response comes back with a stop_reason. This field — not the text — tells you what to do next. The four values are:
end_turn— Claude finished. The loop is over.tool_use— Claude wants a tool run. Execute it and continue.max_tokens— output was truncated by the limit.stop_sequence— a custom stop sequence was hit.
Your loop is really just a decision based on this one field.
if response.stop_reason == "end_turn":
# Done — return the answer
...
elif response.stop_reason == "tool_use":
# Run the requested tool(s), then loop again
...Defining a Tool
A tool is a function you let Claude call. You describe it with a name, a description, and a JSON Schema for its inputs.
The description is the most important part — Claude reads it to decide when to use the tool. Be clear about its purpose, its inputs, and when it applies.
Claude never runs your tool itself. It only asks for it; your code does the actual work and reports back.
tools = [
{
"name": "get_weather",
"description": "Get the current weather for a city. "
"Call this when the user asks about weather "
"or temperature.",
"input_schema": {
"type": "object",
"properties": {
"city": {"type": "string", "description": "City name"}
},
"required": ["city"],
},
}
]When Claude Asks for a Tool
When stop_reason is tool_use, the response content contains a tool_use block. It carries:
- an
id— used to match the result back to the request, - a
name— which tool to run, - an
input— the arguments, already parsed as an object.
Claude can ask for several tools in one response. Run them all before continuing.
for block in response.content:
if block.type == "tool_use":
print(block.name) # "get_weather"
print(block.input) # {"city": "Paris"}
print(block.id) # "toolu_01A..." -> needed for the resultSending the Result Back
To continue, you append two things to the history:
- The assistant's full
response.content(so thetool_useblock is preserved). - A new
usermessage holding atool_resultblock.
Each tool_result must include the matching tool_use_id. Then you call the API again — that's one turn of the loop.
result = run_tool(block.name, block.input)
messages.append({"role": "assistant", "content": response.content})
messages.append({
"role": "user",
"content": [{
"type": "tool_result",
"tool_use_id": block.id, # must match the tool_use id
"content": result,
}],
})The Full Loop in Code
Put it together and the agent is a short while loop:
- Call the API with the full history.
- If
stop_reasonisend_turn, break. - Otherwise run the requested tools, append the results, and loop.
The model drives the decisions; your code just runs the tools and carries the history.
while True:
response = client.messages.create(
model="claude-opus-4-8", max_tokens=1024,
tools=tools, messages=messages,
)
if response.stop_reason == "end_turn":
break
messages.append({"role": "assistant", "content": response.content})
results = [
{"type": "tool_result", "tool_use_id": b.id,
"content": run_tool(b.name, b.input)}
for b in response.content if b.type == "tool_use"
]
messages.append({"role": "user", "content": results})Terminate on stop_reason, Not Text
Here is the rule that separates a robust agent from a fragile one: always terminate on stop_reason, never by reading the text.
Scanning Claude's output for words like "done", "finished", or "complete" is a classic anti-pattern. The model might say "I'm not done yet" or mention the word "done" in a sentence, and your loop breaks at the wrong moment.
The stop_reason field is the one reliable signal. Trust it.
# WRONG — fragile text parsing
if "done" in response_text.lower():
break
# RIGHT — structural signal
if response.stop_reason == "end_turn":
breakIteration Caps Are a Safety Net
It's wise to add a maximum-iteration counter so a misbehaving loop can't run forever. But understand its role: a cap is a safety net, not the primary way you stop.
The primary stop mechanism is always stop_reason == end_turn. The cap only catches the rare runaway case.
Treating an arbitrary iteration cap as your main stop condition is an anti-pattern — it cuts off legitimate work that just needed one more turn.
MAX_ITERS = 20 # safety net only
for _ in range(MAX_ITERS):
response = client.messages.create(...)
if response.stop_reason == "end_turn":
break # the REAL stop condition
# ... run tools, append results ...Model-Driven Decisions, Coded Guarantees
In the agentic loop, the model decides what to do: which tool to call, with what inputs, and when to stop. That flexibility is the whole point of an agent.
Reserve hard code for the things you must guarantee — for example, a deterministic check that a refund can't exceed a policy limit, or that an action only runs after identity is verified.
Let the model plan; let your code enforce. Don't hard-code the trajectory, and don't ask a prompt to enforce a critical rule.
Handling the Other Stop Reasons
Two stop reasons are easy to forget but matter in production:
max_tokens— the output hit the limit and is truncated. Raisemax_tokensor stream, then retry; don't treat partial output as final.stop_sequence— a custom stop sequence you configured was matched.
A complete loop branches on all four values. Silently ignoring max_tokens leads to cut-off answers and broken tool calls.
if response.stop_reason == "end_turn":
finish()
elif response.stop_reason == "tool_use":
run_tools_and_continue()
elif response.stop_reason == "max_tokens":
# truncated — raise max_tokens / stream and retry
handle_truncation()
elif response.stop_reason == "stop_sequence":
handle_stop_sequence()Quick Check
Test your understanding of how to terminate the agentic loop.
Recap: The Agentic Loop
You now know the engine behind every agent:
- Request the API with the full history every turn — the model keeps no state.
- Inspect
stop_reason:end_turn(done),tool_use(run tools),max_tokens(truncated),stop_sequence. - On
tool_use, run the tools and append eachtool_resultwith its matchingtool_use_id. - Repeat until
end_turn.
Terminate on stop_reason, never by parsing text. Iteration caps are a safety net only. Let the model make decisions; reserve hard code for guarantees.
الأسئلة الشائعة
هل درس «نظرة عامة على الحلقة الوكيلة» مجاني؟
نعم — نص درس «نظرة عامة على الحلقة الوكيلة» كامل متاح مجاناً هنا على الويب. لتمرينه بشكل تفاعلي (محرر أكواد مدمج ومدرس ذكاء اصطناعي متاح 24/7) وفتح باقي دورة Claude Architect، انتقل إلى CoddyKit PRO. تتضمن دورة Claude Architect 4 دروس في المجموع.
ماذا ستتعلم في «نظرة عامة على الحلقة الوكيلة»؟
request، وفحص stop_reason، وتشغيل الأدوات، والتكرار تتمرن على Claude Architect مع أكواد عملية تشغلها مباشرة في المتصفح، ومدرس ذكاء اصطناعي متاح 24/7 يجيب على أسئلتك أثناء عملك.
هل أحتاج إلى خبرة سابقة لأبدأ Claude Architect؟
لا تُشترط خبرة سابقة. Claude Architect على CoddyKit منظم للمبتدئين حتى المتقدمين، لذا يمكنك البدء من هنا أو من البداية والتقدم بسرعتك الخاصة. هذا هو الدرس 4 من أصل 4.
كم من الوقت يستغرق درس «نظرة عامة على الحلقة الوكيلة»؟
معظم دروس CoddyKit تستغرق حوالي 5–10 دقائق. كل منها موجز وتفاعلي، لذا تحرز تقدماً مستمراً وتستأنف من حيث توقفت عبر الويب والتطبيق.
هل يمكنني كتابة وتشغيل أكواد في درس Claude Architect هذا؟
نعم. كل درس في Claude Architect يتضمن محرر أكواد مدمج، لذا تكتب وتشغل أكواداً حقيقية مباشرة في متصفحك وتحصل على تعليقات فورية من الذكاء الاصطناعي — بدون إعداد محلي.
جميع الدروس في هذه الدورة
- ما الذي يجعل النظام وكيلًا
- القرارات التي يقودها النموذج مقابل القرارات المبرمجة مسبقًا
- متى تستخدم وكيلًا
- نظرة عامة على الحلقة الوكيلة