Two default capabilities put the web within the agent’s reach: `web_fetch` reads a specific page, and `web_search` looks things up. Both are on by default.

## web\_fetch

`web_fetch` performs an HTTP GET on a URL, reduces the response to text (stripping HTML to plain content, capped so a huge page does not overwhelm the model), and asks a small, fast summarizer model to answer your prompt over that content. It returns the answer, not the raw page, so a long article never floods the conversation. Fetched content is cached for 15 minutes, so repeated fetches of the same URL are fast while each prompt is answered fresh.

The tool takes a `url` and an optional `prompt`. With a prompt, the summarizer answers over the page; leave the prompt empty and it returns the page text verbatim instead. Only `http` and `https` URLs are allowed.

### The summarizer model

By default the summarizer runs on the small, fast model for the main agent’s provider, so its credentials line up with the main model (on Amazon Bedrock, the summarizer follows the main model’s family, Anthropic-on-Bedrock or OpenAI-on-Bedrock). Override it with `builtin_tools={"web_fetch": {"model": ...}}`, which takes the same forms as `model`:

(( tab "Strands harness" ))
(( tab "Python" ))
```python
from strands_harness import create_harness

agent = create_harness(builtin_tools={"web_fetch": {"model": "bedrock/global.anthropic.claude-haiku-4-5-20251001-v1:0"}})
```
(( /tab "Python" ))

(( tab "TypeScript" ))
```typescript
import { createHarness } from '@strands-agents/harness'

const agent = await createHarness({
  builtinTools: { web_fetch: { model: 'bedrock/global.anthropic.claude-haiku-4-5-20251001-v1:0' } },
})
```
(( /tab "TypeScript" ))
(( /tab "Strands harness" ))

(( tab "SDK" ))
(( tab "Python" ))
```python
# pip install strands-agents
from strands import Agent
from strands.vended_tools import web_fetch

# No summarizer-model override in the Strands Harness SDK; web_fetch returns page text
agent = Agent(tools=[web_fetch])
```
(( /tab "Python" ))

(( tab "TypeScript" ))
```typescript
// npm install @strands-agents/sdk
import { Agent } from '@strands-agents/sdk'
import { httpRequest } from '@strands-agents/sdk/vended-tools/http-request'

// No web_fetch or summarizer model; httpRequest returns raw HTTP
const agent = new Agent({ tools: [httpRequest] })
```
(( /tab "TypeScript" ))
(( /tab "SDK" ))

## web\_search

`web_search` lets the agent look things up while it answers. It isn’t a separate tool: it turns on the web search built into the model provider. OpenAI, Anthropic, Google, and the GPT-5 and GPT-6 models on `bedrock-mantle` have one.

For models that don’t provide web search, the harness logs a message and builds the agent without it. If you asked for it explicitly in `builtin_tools`, you get an error instead, so the request doesn’t silently do nothing.

To search with those models anyway, set `{"web_search": "exa"}` in `builtin_tools`. The harness then searches through [Exa](https://exa.ai) instead, on any model, including ones with their own search. No setup is needed to get started, and setting `EXA_API_KEY` lifts the free tier’s rate limit. Exa is a third party, so every search query is sent to Exa and handled under its terms; weigh that before using it for sensitive work. You can also connect the MCP server of your preferred search provider instead; see [connect MCP servers](/pr-cms-5317/docs/user-guide/harness/configure/mcp-servers/index.md).

## Selecting them

Both are selected by name through `builtin_tools`. To turn either off, leave it out of the list or set it to `False`; see [add tools and instructions](/pr-cms-5317/docs/user-guide/harness/configure/tools-and-instructions/index.md) for how selection works. To change the summarizer model, see [choose a model and reasoning](/pr-cms-5317/docs/user-guide/harness/configure/model/index.md).

## Implementation

### Python

- [harness-sdk/harness-py/src/strands_harness/tools/web_fetch.py](https://github.com/strands-agents/harness-sdk/blob/main/harness-py/src/strands_harness/tools/web_fetch.py)
- [harness-sdk/harness-py/src/strands_harness/models.py](https://github.com/strands-agents/harness-sdk/blob/main/harness-py/src/strands_harness/models.py)

### TypeScript

- [harness-sdk/harness-ts/src/tools/web-fetch.ts](https://github.com/strands-agents/harness-sdk/blob/main/harness-ts/src/tools/web-fetch.ts)