Crate llm_browser_testkit 

LLM-driven browser test framework.

Provides reusable building blocks for browser-based test scenarios:

• Browser client via Chrome DevTools Protocol (headless)
• LLM client for natural language element targeting and assertions
• A2A agent integration for agent-to-agent communication
• MCP client/server integration for tool-calling
• Cost tracking, token counting, and budget enforcement
• Declarative TOML scenario runner
• #[browser_test] macros for cargo test integration

Re-exports

pub use costs::LlmResponse;

pub use costs::LlmUsage;

Modules

a2a

A2A agent protocol client. A2A (Agent-to-Agent) protocol client.

budgets

Budget tracking and enforcement. Budget tracking and enforcement.

costs

Cost calculation, usage tracking, and pricing. Cost calculation, usage tracking, and pricing logic.

endpoints

Endpoint registry and routing resolver. Endpoint registry — resolves named endpoints and task-type routing.

mcp_client

MCP client for connecting to external MCP servers. MCP (Model Context Protocol) client.

mcp_server

MCP server for exposing the framework as an MCP server. MCP server exposure — exposes the framework as an MCP server.

reporting

Cost and token report printer. Cost and token report printer.

runner

Step-by-step scenario executor (navigate, click, type, wait, assert).

scenario

Declarative TOML-based test scenario types. Scenario types for human-readable browser test case definitions.

Structs

LlmConfig

Configuration for the LLM client — bundles URL, model, auth, timeouts, and provider-specific options into a single struct passed everywhere.

Constants

DOM_EXTRACT_JS

JavaScript to extract interactive elements from the current page. Returns a JSON array of objects with tag, selector, and label.

Functions

base_url

Returns the target base URL from HARNESS_BROWSER_BASE_URL env, defaulting to http://localhost:4200.

browser_headless

Returns whether to run the browser in headless mode from HARNESS_BROWSER_HEADLESS env, defaulting to true.

http_client

Builds a reqwest::Client with the given timeout.

llm_base_url

Returns the LLM server base URL from HARNESS_LLM_TEST_URL env, defaulting to http://localhost:8080.

llm_chat

Sends a chat completion request to the LLM.

llm_chat_with_usage

Sends a chat completion request to the LLM and returns both the content and token usage from the API response.

llm_model

Returns the LLM model name from HARNESS_LLM_TEST_MODEL env, defaulting to deepseek.

parse_headers_env

Parses HARNESS_LLM_HEADERS env var (JSON object) into a header map.

truncate

Truncates a string to the given maximum length, appending a marker if truncation occurred.