`kagi fastgpt`

Answer queries using Kagi's FastGPT API for quick, factual responses.

Synopsis

kagi fastgpt [OPTIONS] <QUERY>

The kagi fastgpt command queries Kagi's FastGPT API, which provides quick, factual answers optimized for speed and accuracy. Unlike the Assistant which maintains conversation threads, FastGPT is designed for single-question answering.

Key characteristics:

Fast response times
Factual, concise answers
No conversation state
API-based (consumes credit)

Authentication

Required: KAGI_API_TOKEN

FastGPT currently uses Kagi's legacy /api/v0 API with Bot auth. It requires API access and consumes API credit per request.

Arguments

`<QUERY>` (Required)

The question or query to answer.

Example:

kagi fastgpt "What is the capital of France?"
kagi fastgpt "Explain machine learning in simple terms"

Options

`--cache <BOOL>`

Enable or disable response caching.

Values: true, false Default: true

When enabled, identical queries may return cached responses for faster results and reduced API usage.

Example:

kagi fastgpt "What is Rust?" --cache false

`--web-search <BOOL>`

Enable web search augmentation.

Values: true Default: true (web search enabled)

Note: Kagi's documentation notes that values other than true for --web-search are currently unsupported in practice. Passing --web-search false is rejected client-side with an explanatory error.

{
  "meta": {
    "id": "req-123",
    "node": "us-east",
    "ms": 275
  },
  "data": {
    "output": "The answer to your question...",
    "tokens": 57,
    "references": []
  }
}

Fields

Field	Type	Description
`meta`	object	Request metadata from the API
`data.output`	string	FastGPT's answer
`data.tokens`	integer	Token count reported by the API
`data.references`	array	Supporting references when available

Examples

Basic Queries

# Factual question
kagi fastgpt "What is the speed of light?"

# Explanation
kagi fastgpt "How does photosynthesis work?"

# Comparison
kagi fastgpt "What's the difference between TCP and UDP?"

Processing Output

# Extract just the answer
kagi fastgpt "What is Docker?" | jq -r '.data.output'

# Save response
kagi fastgpt "Explain blockchain" > blockchain-explanation.json

# Use in scripts
ANSWER=$(kagi fastgpt "What is $TECHNOLOGY?" | jq -r '.data.output')
echo "Technology: $TECHNOLOGY"
echo "Explanation: $ANSWER"

Quick Reference Tool

#!/bin/bash
# quick-answer.sh

TERM="$1"
[ -z "$TERM" ] && { echo "Usage: quick-answer.sh <term>"; exit 1; }

echo "🔍 Quick answer for: $TERM"
echo ""
kagi fastgpt "What is $TERM?" | jq -r '.data.output'

Exit Codes

Code	Meaning
0	Success - answer received
1	Error - see stderr

Common errors:

Missing API token
Insufficient API credit
Rate limiting
Network error

Comparison with Assistant

Feature	FastGPT	Assistant
Token	API	Session
Speed	Faster	Slightly slower
Conversations	Single query	Threaded
Cost	API credit	Included with subscription
Use case	Quick facts	Complex discussions

When to Use FastGPT

Good for:

Quick factual questions
Simple explanations
Single-turn queries
Automated workflows
Cost-sensitive operations

Not ideal for:

Multi-turn conversations
Complex reasoning chains
Context-dependent queries
Creative writing

Best Practices

Clear Questions

# Good - specific
kagi fastgpt "What are the main differences between Python 2 and Python 3?"

# Less effective - vague
kagi fastgpt "Python"

Error Handling

if ANSWER=$(kagi fastgpt "Question" 2>/dev/null | jq -r '.data.output'); then
  echo "Answer: $ANSWER"
else
  echo "Failed to get answer - check API credit"
fi

Caching Strategy

# For frequently asked questions, caching reduces cost
kagi fastgpt "What is REST?" --cache true

# For time-sensitive queries, disable caching
kagi fastgpt "What is the current weather in Tokyo?" --cache false