| Setting | Value |
|---|---|
| Coding Tool | Claude |
| Framework | cURL |
| Use Case | Web search tool |
| Search Type | Auto - Balanced relevance and speed (~1 second) |
| Content | Full text |
| Project Description: job search, rentals, real estate, etc. |
export EXA_API_KEY="YOUR_API_KEY"EXA_API_KEY=YOUR_API_KEYGive Claude Code real-time web search, code context, and company research with Exa MCP.
Run in terminal:
claude mcp add --transport http exa https://mcp.exa.ai/mcp?exaApiKey=1d5eb8ee-ade7-4d6b-8c09-725747467194Tool enablement (optional):
Add a tools= query param to the MCP URL.
Enable specific tools:
https://mcp.exa.ai/mcp?exaApiKey=1d5eb8ee-ade7-4d6b-8c09-725747467194&tools=web_search_exa,get_code_context_exa,people_search_exa
Enable all tools:
https://mcp.exa.ai/mcp?exaApiKey=1d5eb8ee-ade7-4d6b-8c09-725747467194&tools=web_search_exa,web_search_advanced_exa,get_code_context_exa,crawling_exa,company_research_exa,people_search_exa,deep_researcher_start,deep_researcher_check
Your API key: 1d5eb8ee-ade7-4d6b-8c09-725747467194
Manage keys at dashboard.exa.ai/api-keys.
Troubleshooting: if tools don't appear, restart your MCP client after updating the config.
📖 Full docs: docs.exa.ai/reference/exa-mcp
curl -X POST 'https://api.exa.ai/search' \
-H 'x-api-key: YOUR_API_KEY' \
-H 'Content-Type: application/json' \
-d '{
"query": "latest developments in AI safety research",
"type": "auto",
"num_results": 10,
"contents": {
"text": {
"max_characters": 20000
}
}
}'Function calling (also known as tool use) allows your AI agent to dynamically decide when to search the web based on the conversation context. Instead of searching on every request, the LLM intelligently determines when real-time information would improve its response—making your agent more efficient and accurate.
Why use function calling with Exa?
- Your agent can ground responses in current, factual information
- Reduces hallucinations by fetching real sources when needed
- Enables multi-step reasoning where the agent searches, analyzes, and responds
📚 Full documentation: https://docs.exa.ai/reference/openai-tool-calling
import json
from openai import OpenAI
from exa_py import Exa
openai = OpenAI()
exa = Exa()
tools = [{
"type": "function",
"function": {
"name": "exa_search",
"description": "Search the web for current information.",
"parameters": {
"type": "object",
"properties": {"query": {"type": "string", "description": "Search query"}},
"required": ["query"]
}
}
}]
def exa_search(query: str) -> str:
results = exa.search_and_contents(query, type="auto", num_results=10, text={"max_characters": 20000})
return "\n".join([f"{r.title}: {r.url}" for r in results.results])
messages = [{"role": "user", "content": "What's the latest in AI safety?"}]
response = openai.chat.completions.create(model="gpt-4o", messages=messages, tools=tools)
if response.choices[0].message.tool_calls:
tool_call = response.choices[0].message.tool_calls[0]
search_results = exa_search(json.loads(tool_call.function.arguments)["query"])
messages.append(response.choices[0].message)
messages.append({"role": "tool", "tool_call_id": tool_call.id, "content": search_results})
final = openai.chat.completions.create(model="gpt-4o", messages=messages)
print(final.choices[0].message.content)import anthropic
from exa_py import Exa
client = anthropic.Anthropic()
exa = Exa()
tools = [{
"name": "exa_search",
"description": "Search the web for current information.",
"input_schema": {
"type": "object",
"properties": {"query": {"type": "string", "description": "Search query"}},
"required": ["query"]
}
}]
def exa_search(query: str) -> str:
results = exa.search_and_contents(query, type="auto", num_results=10, text={"max_characters": 20000})
return "\n".join([f"{r.title}: {r.url}" for r in results.results])
messages = [{"role": "user", "content": "Latest quantum computing developments?"}]
response = client.messages.create(model="claude-sonnet-4-20250514", max_tokens=4096, tools=tools, messages=messages)
if response.stop_reason == "tool_use":
tool_use = next(b for b in response.content if b.type == "tool_use")
tool_result = exa_search(tool_use.input["query"])
messages.append({"role": "assistant", "content": response.content})
messages.append({"role": "user", "content": [{"type": "tool_result", "tool_use_id": tool_use.id, "content": tool_result}]})
final = client.messages.create(model="claude-sonnet-4-20250514", max_tokens=4096, tools=tools, messages=messages)
print(final.content[0].text)| Type | Best For | Speed | Depth |
|---|---|---|---|
fast |
Real-time apps, autocomplete, quick lookups | Fastest | Basic |
auto |
Most queries - balanced relevance & speed | Medium | Smart |
deep |
Research, enrichment, thorough results | Slow | Deep |
deep-reasoning |
Complex research, multi-step reasoning | Slowest | Deepest |
Tip: type="auto" works well for most queries. Use type="deep" when you need thorough research results or structured outputs with field-level grounding.
Choose ONE content type per request (not both):
| Type | Config | Best For |
|---|---|---|
| Text | "text": {"max_characters": 20000} |
Full content extraction, RAG |
| Highlights | "highlights": {"max_characters": 4000} |
Snippets, summaries, lower cost |
text: true (full page text) can significantly increase token count, leading to slower and more expensive LLM calls. To mitigate:
- Add
max_characterslimit:"text": {"max_characters": 10000} - Use
highlightsinstead if you don't need contiguous text
When to use text vs highlights:
- Text - When you need untruncated, contiguous content (e.g., code snippets, full articles, documentation)
- Highlights - When you need key excerpts and don't need the full context (e.g., summaries, Q&A, general research)
Usually not needed - Exa's neural search finds relevant results without domain restrictions.
When to use:
- Targeting specific authoritative sources
- Excluding low-quality domains from results
Example:
{
"includeDomains": ["arxiv.org", "github.com"],
"excludeDomains": ["pinterest.com"]
}Note: includeDomains and excludeDomains can be used together to include a broad domain while excluding specific subdomains (e.g., "includeDomains": ["vercel.com"], "excludeDomains": ["community.vercel.com"]).
{
"query": "latest developments in AI safety research",
"num_results": 10,
"contents": {
"text": {
"max_characters": 20000
}
}
}Tips:
- Use
type: "auto"for most queries - Great for building search-powered chatbots or agents
- Combine with contents for RAG workflows
Use category filters to search dedicated indexes. Each category returns only that content type.
Note: Categories can be restrictive. If you're not getting enough results, try searching without a category first, then add one if needed.
Find people by role, expertise, or what they work on
curl -X POST 'https://api.exa.ai/search' \
-H 'x-api-key: YOUR_API_KEY' \
-H 'Content-Type: application/json' \
-d '{
"query": "software engineer distributed systems",
"category": "people",
"type": "auto",
"num_results": 10
}'Tips:
- Use SINGULAR form
- Describe what they work on
- No date/text filters supported
Find companies by industry, criteria, or attributes
curl -X POST 'https://api.exa.ai/search' \
-H 'x-api-key: YOUR_API_KEY' \
-H 'Content-Type: application/json' \
-d '{
"query": "AI startup healthcare",
"category": "company",
"type": "auto",
"num_results": 10
}'Tips:
- Use SINGULAR form
- Simple entity queries
- Returns company objects, not articles
News articles
curl -X POST 'https://api.exa.ai/search' \
-H 'x-api-key: YOUR_API_KEY' \
-H 'Content-Type: application/json' \
-d '{
"query": "OpenAI announcements",
"category": "news",
"type": "auto",
"num_results": 10,
"contents": {
"text": {
"max_characters": 20000
}
}
}'Tips:
- Use livecrawl: "preferred" for breaking news
- Avoid date filters unless required
Academic papers
curl -X POST 'https://api.exa.ai/search' \
-H 'x-api-key: YOUR_API_KEY' \
-H 'Content-Type: application/json' \
-d '{
"query": "transformer architecture improvements",
"category": "research paper",
"type": "auto",
"num_results": 10,
"contents": {
"text": {
"max_characters": 20000
}
}
}'Tips:
- Use type: "auto" for most queries
- Includes arxiv.org, paperswithcode.com, and other academic sources
Twitter/X posts
curl -X POST 'https://api.exa.ai/search' \
-H 'x-api-key: YOUR_API_KEY' \
-H 'Content-Type: application/json' \
-d '{
"query": "AI safety discussion",
"category": "tweet",
"type": "auto",
"num_results": 10,
"contents": {
"text": {
"max_characters": 20000
}
}
}'Tips:
- Good for real-time discussions
- Captures public sentiment
maxAgeHours sets the maximum acceptable age (in hours) for cached content. If the cached version is older than this threshold, Exa will livecrawl the page to get fresh content.
| Value | Behavior | Best For |
|---|---|---|
| 24 | Use cache if less than 24 hours old, otherwise livecrawl | Daily-fresh content |
| 1 | Use cache if less than 1 hour old, otherwise livecrawl | Near real-time data |
| 0 | Always livecrawl (ignore cache entirely) | Real-time data where cached content is unusable |
| -1 | Never livecrawl (cache only) | Maximum speed, historical/static content |
| (omit) | Default behavior (livecrawl as fallback if no cache exists) | Recommended — balanced speed and freshness |
When LiveCrawl Isn't Necessary: Cached data is sufficient for many queries, especially for historical topics or educational content. These subjects rarely change, so reliable cached results can provide accurate information quickly.
See maxAgeHours docs for more details.
Beyond /search, Exa offers these endpoints:
| Endpoint | Description | Docs |
|---|---|---|
/contents |
Get contents for known URLs | Docs |
/answer |
Q&A with citations from web search | Docs |
Example - Get contents for URLs:
POST /contents
{
"urls": ["https://example.com/article"],
"text": { "max_characters": 20000 }
}Results not relevant?
- Try
type: "auto"- most balanced option - Try
type: "deep"- runs multiple query variations and ranks the combined results - Refine query - use singular form, be specific
- Check category matches your use case
Need structured data from search?
- Use
type: "deep"ortype: "deep-reasoning"withoutputSchema - Define the fields you need in the schema — Exa returns grounded JSON with citations
Results too slow?
- Use
type: "fast" - Reduce
num_results - Skip contents if you only need URLs
No results?
- Remove filters (date, domain restrictions)
- Simplify query
- Try
type: "auto"- has fallback mechanisms
- Docs: https://exa.ai/docs
- Dashboard: https://dashboard.exa.ai
- API Status: https://status.exa.ai