Agents
Agents are instruction-driven, model-powered reasoning components that follow a plan → act → observe → repeat loop. They use an LLM to decide the next action, call tools when needed, and return structured output in TEXT, MARKDOWN, or JSON format.
Setup
pip install aixplain
from aixplain import Aixplain
aix = Aixplain(api_key="YOUR_API_KEY")
Quick start
Create and run a minimal agent to validate your setup:
agent = aix.Agent(
name="Hello Agent",
description="Answers general questions clearly and concisely.",
instructions="You are a helpful assistant.",
)
agent.save()
response = agent.run(query="What is machine learning?")
print(response.data.output)
print(agent.path)
agent.save() transitions the agent from DRAFT to ONBOARDED state and makes it callable.
How it works
Each run executes a reasoning loop:
1. INIT → Load config, validate input, process variables
2. REASONING LOOP ⟲
├─> LLM plans next action
├─> Execute tools (if needed)
├─> Evaluate results
└─> Repeat until complete or max_iterations reached
3. RETURN → AgentResponse with output + metadata
The LLM autonomously decides which tools to call and when. Runs continue until the task is complete or max_iterations is hit.
Agent states
| State | Description |
|---|---|
DRAFT | Created but not persisted. Call agent.save() to promote. |
ONBOARDED | Persisted and production-ready. |
Tools
Tools extend an agent beyond text generation. The agent decides autonomously when to invoke them.
# Marketplace tool
web_search_tool = aix.Tool.get("tavily/tavily-search-api")
# Model used as a tool
translation_model = aix.Model.get("google/translate-multi-lingual")
Pass tools at agent creation:
INSTRUCTIONS = """
You are a technical documentation assistant.
Think step-by-step when solving problems. Explain non-obvious choices.
Use tools only when internal knowledge is insufficient.
Prefer official sources when citing.
"""
agent = aix.Agent(
name="Research Agent",
description="Researches topics using web search.",
instructions=INSTRUCTIONS,
tools=[web_search_tool],
)
agent.save()
response = agent.run(query="What are the latest developments in AI safety?")
print(response.data.output)
You can test a tool in isolation before attaching it:
print(web_search_tool.list_actions())
response = web_search_tool.run(data="What is aiXplain?")
print(response.data)
If the agent ignores a tool, check response.data.steps for what it attempted, then tighten the tool's name and description. If total parameters across all tools exceed 100, optional ones may be silently dropped — mark only the ones you need as required.
LLM configuration
The default model is GPT-4o Mini. Override it at agent creation:
# Option A: Model ID
SONNET_MODEL_ID = "67be216bd8f6a65d6f74d5e9"
agent = aix.Agent(
name="Sonnet Agent",
description="...",
llm=aix.Model.get(SONNET_MODEL_ID),
)
# Option B: Fine-grained parameters via the inputs proxy
llm = aix.Model.get("openai/gpt-4o")
llm.inputs.temperature = 1
llm.inputs.max_tokens = 100_000
agent = aix.Agent(
name="Custom LLM Agent",
description="...",
llm=llm,
)
Choose an LLM based on: context window size, reasoning depth, latency requirements, cost per 1M tokens, tool-calling reliability, and multilingual quality.
Output format
Available formats: text (default) | markdown | json.
When using json, pass an expected_output schema. Three formats are accepted:
from pydantic import BaseModel
from typing import List, Dict
# Option 1: Text description of the shape
expected_output = """{"name": "string", "calories": "string"}"""
# Option 2: Dict
expected_output = {"name": "string", "calories": "string"}
# Option 3: Pydantic model (recommended — adds type validation)
class RecipeOutput(BaseModel):
name: str
description: str
ingredients: List[str]
instructions: str
nutrition: Dict[str, str]
expected_output = RecipeOutput
recipe_agent = aix.Agent(
name="Recipe Structurer",
description="Culinary assistant that returns structured recipes.",
instructions="Extract and organise recipe data into the required JSON shape. Use web search to fill gaps.",
tools=[web_search_tool],
output_format="json",
expected_output=expected_output,
)
recipe_agent.save()
response = recipe_agent.run("Chocolate cake recipe")
print(response.data.output)
Runtime parameters
agent.run() accepts the following parameters:
| Parameter | Type | Default | Description |
|---|---|---|---|
query | str | — | Main task or question. |
content | dict | list | None | Text, file paths, or URLs. Use dict for {{template}} substitution. |
data | any | None | Alternative to query + content — use one or the other. |
variables | dict | None | Values substituted into {{placeholders}} in instructions / description. |
session_id | str | None | Resume a stateful session (14-day retention). |
history | list | None | Inject prior turns without a session. |
max_tokens | int | 2048 | Output token cap per run. |
max_iterations | int | 5 | Max reasoning loop iterations. |
runResponseGeneration | bool | True | Whether to generate a final response after tool steps. |
name | str | "model_process" | Execution label in logs. |
trace_request | bool | False | Return a request ID for backend tracing. |
progress_format | str | None | None | "status" (single line) or "logs" (timeline). None disables output. |
progress_verbosity | int | 1 | Detail level: 1 minimal, 2 includes thoughts, 3 full I/O. |
progress_truncate | bool | True | Truncate long text in progress output. |
timeout | int | 300 | Seconds to poll before the SDK stops waiting. The agent may continue server-side. |
wait_time | float | 0.5 | Seconds between polling checks. |
Understanding max_tokens
Both llm.inputs.max_tokens and the per-run max_tokens cap output tokens only (not input/context). They are independent levers:
# Persistent default — applies to every invocation by this agent
llm.inputs.max_tokens = 100_000
# Per-run override — applies to this execution only
response = agent.run(query="...", max_tokens=4000)
Keep caps conservative. Raise max_tokens on a single run first; if truncation is frequent, raise llm.inputs.max_tokens permanently.
Variable substitution
Use {{variable}} placeholders in instructions or description, then supply values at runtime via variables:
agent = aix.Agent(
name="Multilingual Researcher",
description="Research assistant for {{topic}}.",
instructions="""
You are a research assistant specialising in {{topic}}.
Always respond in {{language}}.
Focus on peer-reviewed sources when available.
""",
tools=[web_search_tool],
)
agent.save()
response = agent.run(
query="What are the key challenges?",
variables={"topic": "quantum computing", "language": "Spanish"},
)
print(response.data.output)
variables substitution applies to instructions and description only — not to query or content.
Progress streaming
# Disabled (default)
response = agent.run(query="What is machine learning?")
# Compact single-line status
response = agent.run(
query="What is machine learning?",
progress_format="status",
progress_verbosity=1,
)
# Full timestamped log with agent reasoning
response = agent.run(
query="What is machine learning?",
progress_format="logs",
progress_verbosity=2,
progress_truncate=True,
)
| Level | What's shown |
|---|---|
1 | Step names and tool invocations |
2 | Steps + agent reasoning / thoughts |
3 | Full inputs and outputs at every step |
Session management
Pass session_id to persist multi-turn context (stored 14 days, not used for training). Pass history to inject prior turns from an external source.
# Start a session
session_id = agent.generate_session_id()
response = agent.run(query="What is machine learning?", session_id=session_id)
print(response.data.output)
# Follow-up — agent retains context from the first turn
followup = agent.run(query="Give me a practical example.", session_id=session_id)
print(followup.data.output)
# Inject history manually (no server-side memory)
history = [
{"role": "user", "content": "What is the capital of France?"},
{"role": "assistant", "content": "The capital of France is Paris."},
]
response = agent.run("Tell me a fun fact about it.", history=history)
print(response.data.output)
# Seed a new session with existing history
session_id = agent.generate_session_id(history=history)
response = agent.run("Tell me more about that.", session_id=session_id)
print(response.data.output)
Tracing and monitoring
Every run returns structured traces. Use them for debugging and cost tracking:
response = agent.run(query="Summarise this page.", content=["https://en.wikipedia.org/wiki/Freedom"])
# Run outcome
print("Status:", response.status) # SUCCEEDED / FAILED / IN_PROGRESS
print("Output:", response.data.output) # Final answer
print("Completed:", response.completed) # True when run reached a terminal state
print("Error:", response.error_message)
# Reasoning steps
for i, step in enumerate(response.data.steps or []):
print(f"\n--- Step {i+1}: {step.get('agent')} ---")
print("Thought:", step.get("thought"))
print("Action:", step.get("action"))
print("Reason:", step.get("reason"))
for ts in step.get("tool_steps") or []:
print(" Tool:", ts.get("tool"))
print(" Input:", ts.get("input"))
print(" Output:", str(ts.get("output"))[:200], "…")
print(" Error:", ts.get("error"))
# Execution metrics
stats = response.data.executionStats or {}
print("\nAPI calls:", stats.get("api_calls"))
print("Credits:", stats.get("credits"))
print("Runtime:", stats.get("runtime"), "s")
print("Assets used:", stats.get("assets_used"))
print("Session ID:", stats.get("session_id"))
print("Run ID:", stats.get("params", {}).get("id"))
print("Request ID:", stats.get("request_id"))
API key rate limiting
Token-based rate limits support granular control via TokenType:
from aixplain.enums import TokenType
from aixplain.modules import APIKeyLimits
# Limit on combined input + output tokens
limits = APIKeyLimits(
token_limit=100_000,
token_type=TokenType.TOTAL,
)
# Limit on output tokens only (useful for cost control)
limits = APIKeyLimits(
token_limit=50_000,
token_type=TokenType.OUTPUT,
)
TokenType | Tracks |
|---|---|
INPUT | Prompt tokens only |
OUTPUT | Completion tokens only |
TOTAL | Combined input + output |
Save and update
The typical lifecycle is create → save → run → update → save:
agent.output_format = "markdown"
agent.max_iterations = 15
agent.save()
Call agent.save() after any change to name, description, instructions, tools, llm, or output_format.
Troubleshooting
Agent ignores tools
Inspect response.data.steps to see what the agent attempted. Check that the tool's name and description are unambiguous. If total tool parameters exceed 100, optional ones may be silently dropped.
agent reached the maximum number of iterations
The agent hit max_iterations (default 5 for single agents, 30 for team agents). Raise it for complex tasks:
agent.max_iterations = 20
agent.save()
model response was cut off because the maximum token limit was reached
Increase the LLM's persistent token cap:
llm = aix.Model.get("openai/gpt-4o")
llm.inputs.max_tokens = 100_000
agent.llm = llm
agent.save()
Agent response is cropped
The agent's own max_tokens (default 2048) caps the final output, independent of the LLM cap. Raise it:
agent.max_tokens = 20_000
agent.save()