llm_browser_testkit/
scenario.rs

1//! Scenario types for human-readable browser test case definitions.
2//!
3//! Scenarios are written in [TOML](https://toml.io) and describe groups of
4//! browser interaction tests with reusable assertion definitions and
5//! configurable test-level overrides.
6//!
7//! # Structure
8//!
9//! ```toml
10//! [config]                         # Global defaults
11//! start_url = "/dashboard"
12//!
13//! [[definitions]]                  # Reusable assertion definitions
14//! name = "no_errors"
15//! preset = "no_error_on_page"
16//!
17//! [[test]]                         # Test group
18//! name = "Dashboard Smoke"
19//! start_url = "/dashboard"         # Override global start_url (optional)
20//!
21//! [[test.steps]]                   # Ordered steps — the `kind` field
22//! kind = "navigate"                # determines which other fields apply
23//! url = "/dashboard"
24//!
25//! [[test.steps]]
26//! kind = "click"
27//! target = "the Login button"      # Natural language — LLM resolves to selector
28//!
29//! [[test.steps]]
30//! kind = "assert"
31//! definition = "no_errors"
32//! ```
33//!
34//! ## Step Kinds
35//!
36//! | `kind`        | Required fields  | Optional fields                          |
37//! |---------------|-----------------|------------------------------------------|
38//! | `navigate`    | `url`           | `wait_after_ms`                          |
39//! | `click`       | `target`        | `selector`, `wait_after_ms`              |
40//! | `type`        | `target`, `text`| `selector`, `wait_after_ms`              |
41//! | `wait`        | `target`        | `selector`, `timeout_ms`                 |
42//! | `assert`      | *one of below*  | —                                        |
43//! | `screenshot`  | —               | `path`                                   |
44//! | `agent`       | `agent`, `task` | —                                        |
45//! | `mcp`         | `server`, `tool`| `args`                                   |
46//!
47//! Assert steps require one of: `definition` (references a named
48//! `[[definitions]]` entry), `preset` (built-in preset name), or `prompt`
49//! (custom LLM evaluation prompt).
50
51use std::collections::HashMap;
52
53use serde::Deserialize;
54use serde_json::Value;
55
56/// Top-level scenario file, deserialized from TOML.
57#[derive(Debug, Deserialize)]
58pub struct Scenario {
59    /// Global configuration (overridable per test).
60    #[serde(default)]
61    pub config: ScenarioConfig,
62
63    /// Reusable assertion definitions referenced by name in `assert` steps.
64    #[serde(default)]
65    pub definitions: Vec<AssertDefinition>,
66
67    /// Ordered test groups to execute.
68    #[serde(default)]
69    pub test: Vec<TestGroup>,
70}
71
72/// Global scenario configuration with per-test overridable fields.
73#[derive(Debug, Deserialize, Default, Clone)]
74pub struct ScenarioConfig {
75    /// Base URL for relative navigation.
76    #[serde(default)]
77    pub base_url: Option<String>,
78    /// LLM server base URL (deprecated; prefer `[config.endpoints]`).
79    #[serde(default)]
80    pub llm_url: Option<String>,
81    /// LLM model name (deprecated; prefer `[config.endpoints]`).
82    #[serde(default)]
83    pub llm_model: Option<String>,
84    /// LLM API key (Bearer token).
85    #[serde(default)]
86    pub llm_api_key: Option<String>,
87    /// Custom HTTP headers as JSON key-value pairs.
88    #[serde(default, deserialize_with = "deserialize_headers")]
89    pub llm_headers: HashMap<String, String>,
90    /// Run browser in headless mode.
91    #[serde(default)]
92    pub browser_headless: Option<bool>,
93    /// HTTP Basic Auth username for browser navigation.
94    #[serde(default)]
95    pub browser_basic_auth_user: Option<String>,
96    /// HTTP Basic Auth password for browser navigation.
97    #[serde(default)]
98    pub browser_basic_auth_password: Option<String>,
99    /// HTTP / browser action timeout in seconds.
100    #[serde(default)]
101    pub timeout_secs: Option<u64>,
102    /// Browser viewport width.
103    #[serde(default)]
104    pub viewport_width: Option<u32>,
105    /// Browser viewport height.
106    #[serde(default)]
107    pub viewport_height: Option<u32>,
108    /// Default URL every test auto-navigates to before running its steps.
109    #[serde(default)]
110    pub start_url: Option<String>,
111    /// Whether to auto-navigate to `start_url` before test steps.
112    ///
113    /// Disable when a test starts with click-based navigation.
114    #[serde(default = "default_auto_navigate")]
115    pub auto_navigate: bool,
116    /// LLM temperature (0.0–1.0). Lower = more deterministic.
117    #[serde(default = "default_temperature")]
118    pub temperature: f64,
119    /// Enable thinking/reasoning tokens. `None` means the provider default
120    /// is used (no `thinking` key is sent). Set to `true`/`false` to
121    /// explicitly enable or disable.
122    #[serde(default)]
123    pub thinking: Option<bool>,
124    /// Provider-specific model parameters merged into the chat completion
125    /// request body (e.g. `effort = "high"` for Anthropic).
126    #[serde(default, deserialize_with = "deserialize_model_params")]
127    pub model_params: HashMap<String, Value>,
128    /// Named endpoints (LLM, MCP, A2A agents) with pricing.
129    #[serde(default)]
130    pub endpoints: HashMap<String, EndpointConfig>,
131    /// Global and per-test budgets for cost/token/call limits.
132    #[serde(default)]
133    pub budgets: BudgetsConfig,
134    /// MCP server exposure configuration.
135    #[serde(default)]
136    pub mcp_server: Option<McpServerConfig>,
137    /// A2A agent server exposure configuration.
138    #[serde(default)]
139    pub a2a_server: Option<A2aServerConfig>,
140    /// Whether to continue running the remaining steps of a test after a
141    /// step fails. Default `false` = fail fast: the first failed step ends
142    /// the test and the rest are reported as skipped. Set to `true` to run
143    /// every step (more diagnostics, more LLM cost on broken apps).
144    #[serde(default)]
145    pub continue_on_failure: bool,
146    /// Longest edge (px) of screenshots attached to `screenshot = true`
147    /// assert steps, before they are JPEG-encoded and sent to the vision
148    /// endpoint. Downscaling keeps vision token cost/quality sane.
149    /// Default: 1400.
150    #[serde(default)]
151    pub screenshot_max_dimension: Option<u32>,
152    /// Height cap (px) of page coverage for screenshots attached to
153    /// `screenshot = true` assert steps. The full scrollable page is
154    /// captured, then split into viewport-tall tiles (each sent as its own
155    /// image part, ordered from the top) covering at most this many pixels
156    /// — below-the-fold content stays visible to the vision model at 1:1
157    /// detail while token cost stays bounded. Accepts an absolute pixel
158    /// count (`2880`) or a viewport multiple (`"20x"` = twenty times the
159    /// currently applied viewport height, which follows viewport-matrix
160    /// and per-test overrides). A value below the viewport height is
161    /// raised to it, so the visible viewport is always fully included
162    /// (`0` / `"0x"` therefore means "viewport only", the pre-full-page
163    /// behavior). Default: `"20x"`.
164    #[serde(default, deserialize_with = "deserialize_screenshot_max_height")]
165    pub screenshot_max_height: Option<ScreenshotHeight>,
166    /// Directory for failure artifacts (screenshots, page snapshots).
167    /// Defaults to `artifacts`.
168    #[serde(default)]
169    pub artifacts_dir: Option<String>,
170    /// Optional viewport matrix: when set, every test in the scenario is
171    /// expanded into one variant per viewport (e.g. mobile/tablet/desktop).
172    /// Each variant overrides the test's viewport and gets a ` — <name>`
173    /// suffix on the test name. Per-test budgets apply per variant.
174    #[serde(default)]
175    pub viewport_matrix: Option<ViewportMatrix>,
176    /// Class-name prefixes the `layout_no_issues` scan skips: elements
177    /// whose class matches any prefix are ignored by the fixed-element,
178    /// text-clipped, and overlap checks. Defaults cover the Angular CDK
179    /// screen-reader helpers (`cdk-visually-hidden`,
180    /// `cdk-describedby-message-container`, `cdk-overlay-container`),
181    /// which are intentionally 1x1 / off-screen.
182    #[serde(default = "default_layout_ignore_classes")]
183    pub layout_ignore_classes: Vec<String>,
184    /// Concurrency group for parallel runs across scenario files.
185    /// When several scenario files are run together (`--parallel > 1`),
186    /// files that declare the **same** `concurrency_group` are never
187    /// executed at the same time — use this for files that touch the same
188    /// shared backend state and would interfere if run concurrently. A file
189    /// with no group gets its own implicit group, so distinct files run in
190    /// parallel by default. Only honored when files are passed to the
191    /// runner as a batch; has no effect on the steps within a single file,
192    /// which always run sequentially.
193    #[serde(default)]
194    pub concurrency_group: Option<String>,
195    /// Default for per-endpoint `cache` across all endpoints (default
196    /// `true`). Set to `false` to disable provider-side prompt-cache
197    /// markers globally.
198    #[serde(default)]
199    pub cache: Option<bool>,
200    /// Default for per-endpoint `pricing.cache_pricing` across all
201    /// endpoints (default `true`). Set to `false` to bill all prompt
202    /// tokens at the flat input price instead of cache rates.
203    #[serde(default)]
204    pub cache_pricing: Option<bool>,
205}
206
207/// A list of named viewports a scenario is expanded across.
208#[derive(Debug, Deserialize, Clone, Default)]
209pub struct ViewportMatrix {
210    /// The viewport variants (`{name, width, height}`).
211    #[serde(default)]
212    pub viewports: Vec<ViewportDef>,
213}
214
215/// Height cap for screenshots attached to `screenshot = true` assert
216/// steps: either an absolute pixel count or a multiple of the currently
217/// applied viewport height.
218#[derive(Debug, Clone, PartialEq)]
219pub enum ScreenshotHeight {
220    /// Absolute height in pixels.
221    Pixels(u32),
222    /// Multiple of the active viewport height (e.g. `2x` = twice the
223    /// current viewport's pixel height).
224    ViewportTimes(f64),
225}
226
227/// Ceiling (px) applied when resolving screenshot height specs, so an
228/// absurdly large multiplier can never overflow or produce an unusable
229/// capture.
230const MAX_SCREENSHOT_HEIGHT: u32 = 4_000_000;
231
232impl ScreenshotHeight {
233    /// Resolves this height spec to a pixel value for the given viewport
234    /// height. Multipliers are rounded and clamped to
235    /// [`MAX_SCREENSHOT_HEIGHT`].
236    #[must_use]
237    pub fn to_px(&self, viewport_height: u32) -> u32 {
238        match self {
239            Self::Pixels(px) => *px,
240            Self::ViewportTimes(mult) => {
241                let scaled = f64::from(viewport_height) * mult;
242                #[allow(clippy::cast_possible_truncation, clippy::cast_sign_loss)]
243                let px = scaled
244                    .round()
245                    .max(1.0)
246                    .min(f64::from(MAX_SCREENSHOT_HEIGHT)) as u32;
247                px
248            }
249        }
250    }
251}
252
253/// One named viewport size in a matrix.
254#[derive(Debug, Deserialize, Clone)]
255pub struct ViewportDef {
256    /// Human-readable variant name (appended to test names, e.g.
257    /// `— mobile`).
258    pub name: String,
259    /// Browser viewport width in pixels.
260    pub width: u32,
261    /// Browser viewport height in pixels.
262    pub height: u32,
263}
264
265/// A named endpoint definition with pricing.
266#[derive(Debug, Deserialize, Clone, Default)]
267pub struct EndpointConfig {
268    /// Endpoint type: `llm`, `mcp`, or `a2a`.
269    #[serde(rename = "type")]
270    pub endpoint_type: EndpointType,
271    /// Base URL for the endpoint.
272    #[serde(default)]
273    pub url: Option<String>,
274    /// Model name (LLM endpoints only).
275    #[serde(default)]
276    pub model: Option<String>,
277    /// API key / bearer token.
278    #[serde(default)]
279    pub api_key: Option<String>,
280    /// Custom HTTP headers as JSON key-value pairs.
281    #[serde(default, deserialize_with = "deserialize_headers")]
282    pub headers: HashMap<String, String>,
283    /// Pricing configuration.
284    #[serde(default)]
285    pub pricing: Option<PricingConfig>,
286    /// Automatically fetch exact per-token pricing for this endpoint at
287    /// startup from a provider's public pricing API, filling in any pricing
288    /// fields left unset (explicit `pricing` values win). Defaults to
289    /// `"auto"`: Bedrock endpoints use the AWS Price List and `openrouter.ai`
290    /// URLs use the `OpenRouter` models API; other providers are a no-op.
291    /// Force a source with `"bedrock"` / `"openrouter"`, or disable the
292    /// lookup with `"off"` / `"none"` / `"disabled"`.
293    #[serde(default)]
294    pub pricing_source: Option<String>,
295    /// Task types this endpoint serves by default
296    /// (e.g. `["targeting", "assertion"]`).
297    #[serde(default)]
298    pub default_for: Vec<String>,
299    /// Command to launch an MCP server subprocess (stdio transport).
300    #[serde(default)]
301    pub command: Option<String>,
302    /// Arguments for the MCP server command.
303    #[serde(default)]
304    pub args: Vec<String>,
305    /// Whether this LLM endpoint accepts image parts (vision) in addition
306    /// to text. `assert` steps with `screenshot = true` require a vision
307    /// endpoint.
308    #[serde(default)]
309    pub vision: bool,
310    /// How often a single chat completion against this endpoint is retried
311    /// on transient failures (HTTP 429/5xx, empty 200 bodies, network
312    /// errors) before the fallback chain is tried. Default: 3 (override
313    /// globally with `HARNESS_LLM_CALL_ATTEMPTS`).
314    #[serde(default)]
315    pub max_attempts: Option<u32>,
316    /// Ordered names of other endpoints to try when this endpoint exhausts
317    /// its attempts. Only LLM endpoints are eligible. Useful for pairing a
318    /// cheap primary model with a more powerful/expensive fallback.
319    #[serde(default)]
320    pub fallbacks: Vec<String>,
321    /// LLM provider protocol: `openai` (default, OpenAI-compatible chat
322    /// completions), `azure` (`Azure` `OpenAI`), or `bedrock` (AWS Bedrock
323    /// Converse API; requires the `aws` cargo feature).
324    #[serde(default)]
325    pub provider: Provider,
326    /// `Azure` `OpenAI` deployment name (`provider = "azure"`). Defaults to
327    /// `model` when unset.
328    #[serde(default)]
329    pub deployment: Option<String>,
330    /// `Azure` `OpenAI` API version (`provider = "azure"`). Defaults to
331    /// `2024-10-21`.
332    #[serde(default)]
333    pub api_version: Option<String>,
334    /// Authentication configuration for LLM endpoints (API key, token
335    /// command, Entra ID client credentials / managed identity).
336    #[serde(default)]
337    pub auth: AuthConfig,
338    /// Extra HTTP headers produced by running a command per call, keyed by
339    /// header name. The command's stdout (first line) becomes the header
340    /// value. Provider-agnostic — applies to every LLM provider.
341    #[serde(default, deserialize_with = "deserialize_headers")]
342    pub header_commands: HashMap<String, String>,
343    /// AWS credential settings (`provider = "bedrock"`).
344    #[serde(default)]
345    pub aws: AwsConfig,
346    /// Send provider-side prompt-cache markers from this endpoint
347    /// (default `true`). Only providers that require explicit markers are
348    /// affected: AWS Bedrock gets a `cachePoint` block, and Anthropic-style
349    /// OpenAI-compatible models (model name contains `claude`/`anthropic`,
350    /// e.g. via `OpenRouter`) get a `cache_control: ephemeral` block on the
351    /// system message. `OpenAI`, `Azure`, Groq, xAI and `DeepSeek` cache
352    /// automatically and need no markers. Set to `false` to disable.
353    #[serde(default)]
354    pub cache: Option<bool>,
355}
356
357/// Type discriminator for endpoint configuration.
358#[derive(Debug, Deserialize, Clone, PartialEq, Eq, Default)]
359#[serde(rename_all = "lowercase")]
360pub enum EndpointType {
361    /// OpenAI-compatible LLM API.
362    #[default]
363    Llm,
364    /// Model Context Protocol server.
365    Mcp,
366    /// Agent-to-Agent protocol agent.
367    A2a,
368}
369
370/// LLM provider protocol used by an LLM endpoint.
371#[derive(Debug, Deserialize, Clone, Copy, PartialEq, Eq, Default)]
372#[serde(rename_all = "lowercase")]
373pub enum Provider {
374    /// OpenAI-compatible Chat Completions API
375    /// (`POST <url>/v1/chat/completions`).
376    #[default]
377    Openai,
378    /// `Azure` `OpenAI`
379    /// (`POST <url>/openai/deployments/<deployment>/chat/completions`).
380    Azure,
381    /// AWS Bedrock Converse API (`POST https://bedrock-runtime.<region>
382    /// .amazonaws.com/model/<model>/converse`). Requires the `aws` cargo
383    /// feature; uses the standard AWS credential chain unless overridden.
384    Bedrock,
385}
386
387/// Authentication mode for an LLM endpoint.
388#[derive(Debug, Deserialize, Clone, Copy, PartialEq, Eq, Default)]
389#[serde(rename_all = "kebab-case")]
390pub enum AuthMode {
391    /// Static API key. Sent as `Authorization: Bearer <key>` by default;
392    /// set [`AuthConfig::api_key_header`] (or use the `azure` provider)
393    /// to send it in a different header.
394    #[default]
395    ApiKey,
396    /// Execute a command and use its stdout (first line) as the bearer
397    /// token. Uses the `token_command` field. Provider-agnostic escape
398    /// hatch — e.g. `az account get-access-token …`.
399    TokenCommand,
400    /// Entra ID (`Azure` AD) OAuth 2.0 client-credentials grant: exchanges
401    /// `client_id` + `client_secret` in `tenant_id` for a bearer token.
402    EntraClientCredentials,
403    /// Entra ID managed identity: fetches a bearer token from the IMDS
404    /// endpoint (works on `Azure` VMs / App Service / ACI with a
405    /// system-assigned identity; zero credentials in the config).
406    EntraManagedIdentity,
407}
408
409/// Authentication settings for an LLM endpoint.
410#[derive(Debug, Deserialize, Clone, Default)]
411pub struct AuthConfig {
412    /// Which authentication mode to use. Default: `api-key`.
413    #[serde(default)]
414    pub mode: AuthMode,
415    /// Header name that receives the API key instead of
416    /// `Authorization: Bearer` (`mode = "api-key"`). For example the `Azure`
417    /// `OpenAI` `api-key` header.
418    #[serde(default)]
419    pub api_key_header: Option<String>,
420    /// Command whose stdout (first line) is used as the bearer token
421    /// (`mode = "token-command"`).
422    #[serde(default)]
423    pub token_command: Option<String>,
424    /// Entra tenant id (`mode = "entra-client-credentials"`,
425    /// `"entra-managed-identity"`).
426    #[serde(default)]
427    pub tenant_id: Option<String>,
428    /// Entra client id (`mode = "entra-client-credentials"`).
429    #[serde(default)]
430    pub client_id: Option<String>,
431    /// Entra client secret (`mode = "entra-client-credentials"`).
432    #[serde(default)]
433    pub client_secret: Option<String>,
434    /// Entra token scope. Defaults to
435    /// `https://cognitiveservices.azure.com/.default`.
436    #[serde(default)]
437    pub scope: Option<String>,
438    /// Override for the Entra token endpoint
439    /// (`mode = "entra-client-credentials"`), default
440    /// `https://login.microsoftonline.com`. Also used as the IMDS identity
441    /// endpoint base for `"entra-managed-identity"` (default
442    /// `http://169.254.169.254`). Mainly useful for tests and proxies.
443    #[serde(default)]
444    pub token_url: Option<String>,
445    /// Seconds to reuse a fetched (non-API-key) token before refetching.
446    /// For Entra modes the server-issued expiry is used when available;
447    /// this caps the reuse window. Default 300.
448    #[serde(default)]
449    pub cache_ttl_secs: Option<u64>,
450}
451
452/// AWS credential and region settings for a `bedrock` provider endpoint.
453///
454/// When no explicit access key is given, the standard AWS credential chain
455/// is used (env vars, shared config `~/.aws/config` + `~/.aws/credentials`,
456/// SSO, ECS/IMDS) — the same behavior as the AWS CLI. `profile` selects a
457/// named profile from the shared config, and `region` overrides the chain
458/// default.
459#[derive(Debug, Deserialize, Clone, Default)]
460pub struct AwsConfig {
461    /// Named profile from `~/.aws/config` / `~/.aws/credentials` to use
462    /// (default: the AWS CLI default selection via `AWS_PROFILE` or
463    /// `default`).
464    #[serde(default)]
465    pub profile: Option<String>,
466    /// AWS region (default: `AWS_REGION` env or the profile's region;
467    /// required if neither is set).
468    #[serde(default)]
469    pub region: Option<String>,
470    /// Explicit access key id (bypasses the credential chain).
471    #[serde(default)]
472    pub access_key_id: Option<String>,
473    /// Explicit secret access key (with `access_key_id`).
474    #[serde(default)]
475    pub secret_access_key: Option<String>,
476    /// Optional session token for explicit temporary credentials.
477    #[serde(default)]
478    pub session_token: Option<String>,
479}
480
481/// Pricing configuration for an endpoint.
482#[derive(Debug, Deserialize, Clone, Default)]
483pub struct PricingConfig {
484    /// Cost per 1M input tokens (USD).
485    #[serde(default)]
486    pub input_per_1m_tokens: f64,
487    /// Cost per 1M output tokens (USD).
488    #[serde(default)]
489    pub output_per_1m_tokens: f64,
490    /// Flat cost per call (USD), used for MCP/agent endpoints.
491    #[serde(default)]
492    pub per_call: f64,
493    /// Cost per 1M cached-input (prompt cache read) tokens (USD). When
494    /// unset, `input_per_1m_tokens * cache_read_multiplier` is used.
495    #[serde(default)]
496    pub cached_input_per_1m_tokens: Option<f64>,
497    /// Cost per 1M cache-write (cache creation) input tokens (USD). When
498    /// unset, `input_per_1m_tokens * cache_write_multiplier` is used.
499    #[serde(default)]
500    pub cache_write_per_1m_tokens: Option<f64>,
501    /// Multiplier applied to `input_per_1m_tokens` for cache reads when
502    /// `cached_input_per_1m_tokens` is unset. Default: 0.1.
503    #[serde(default)]
504    pub cache_read_multiplier: Option<f64>,
505    /// Multiplier applied to `input_per_1m_tokens` for cache writes when
506    /// `cache_write_per_1m_tokens` is unset. Default: 1.25.
507    #[serde(default)]
508    pub cache_write_multiplier: Option<f64>,
509    /// Bill cache reads/writes at their cache rates (default `true`). Set
510    /// to `false` to bill every prompt token at the flat input price.
511    #[serde(default)]
512    pub cache_pricing: Option<bool>,
513}
514
515/// Budget limits for test execution.
516#[derive(Debug, Deserialize, Clone, Default)]
517pub struct BudgetsConfig {
518    /// Global budget across all tests in the scenario.
519    #[serde(default)]
520    pub global: Option<BudgetDef>,
521    /// Default per-test budget. Individual tests can override.
522    #[serde(default)]
523    pub per_test_default: Option<BudgetDef>,
524}
525
526/// A budget definition with limits and enforcement mode.
527#[derive(Debug, Deserialize, Clone)]
528pub struct BudgetDef {
529    /// Maximum cost in USD.
530    #[serde(default)]
531    pub max_cost: Option<f64>,
532    /// Maximum total tokens (input + output).
533    #[serde(default)]
534    pub max_tokens: Option<u64>,
535    /// Maximum number of calls (LLM, MCP, agent combined).
536    #[serde(default)]
537    pub max_calls: Option<u64>,
538    /// Enforcement mode: `hard` (abort) or `soft` (warn and continue).
539    #[serde(default)]
540    pub enforcement: Option<BudgetEnforcement>,
541}
542
543/// Budget enforcement strategy.
544#[derive(Debug, Deserialize, Clone, PartialEq, Eq)]
545#[serde(rename_all = "lowercase")]
546pub enum BudgetEnforcement {
547    /// Abort the test or run when budget is exceeded.
548    Hard,
549    /// Log a warning but continue execution.
550    Soft,
551}
552
553/// MCP server exposure configuration.
554#[derive(Debug, Deserialize, Clone)]
555pub struct McpServerConfig {
556    /// Whether to enable the embedded MCP server.
557    #[serde(default)]
558    pub enabled: bool,
559    /// Port to listen on.
560    #[serde(default = "default_mcp_port")]
561    pub port: u16,
562}
563
564const fn default_mcp_port() -> u16 {
565    3000
566}
567
568/// A2A agent server exposure configuration.
569#[derive(Debug, Deserialize, Clone)]
570pub struct A2aServerConfig {
571    /// Whether to enable the embedded A2A agent server.
572    #[serde(default)]
573    pub enabled: bool,
574    /// Port to listen on.
575    #[serde(default = "default_a2a_port")]
576    pub port: u16,
577}
578
579const fn default_a2a_port() -> u16 {
580    3100
581}
582
583fn deserialize_headers<'de, D>(deserializer: D) -> Result<HashMap<String, String>, D::Error>
584where
585    D: serde::Deserializer<'de>,
586{
587    let raw: Option<serde_json::Value> = Option::deserialize(deserializer)?;
588    let Some(json) = raw else {
589        return Ok(HashMap::new());
590    };
591    let serde_json::Value::Object(obj) = json else {
592        return Ok(HashMap::new());
593    };
594    Ok(obj
595        .into_iter()
596        .filter_map(|(k, v)| v.as_str().map(|s| (k, s.to_owned())))
597        .collect())
598}
599
600const fn default_auto_navigate() -> bool {
601    true
602}
603
604fn default_layout_ignore_classes() -> Vec<String> {
605    vec![
606        "cdk-visually-hidden".to_owned(),
607        "cdk-describedby-message-container".to_owned(),
608        "cdk-overlay-container".to_owned(),
609    ]
610}
611
612const fn default_temperature() -> f64 {
613    0.0
614}
615
616fn deserialize_model_params<'de, D>(deserializer: D) -> Result<HashMap<String, Value>, D::Error>
617where
618    D: serde::Deserializer<'de>,
619{
620    #[derive(Deserialize)]
621    #[serde(untagged)]
622    enum Raw {
623        Map(HashMap<String, Value>),
624        Table(HashMap<String, Value>),
625    }
626    let raw: Option<Raw> = Option::deserialize(deserializer)?;
627    Ok(match raw {
628        Some(Raw::Map(m) | Raw::Table(m)) => m,
629        None => HashMap::new(),
630    })
631}
632
633fn deserialize_screenshot_max_height<'de, D>(
634    deserializer: D,
635) -> Result<Option<ScreenshotHeight>, D::Error>
636where
637    D: serde::Deserializer<'de>,
638{
639    let raw: Option<serde_json::Value> = Option::deserialize(deserializer)?;
640    match raw {
641        None => Ok(None),
642        Some(value) => match value.as_u64() {
643            // Integer: absolute pixel count.
644            Some(px) if px <= u64::from(MAX_SCREENSHOT_HEIGHT) => {
645                #[allow(clippy::cast_possible_truncation, clippy::cast_sign_loss)]
646                Ok(Some(ScreenshotHeight::Pixels(px as u32)))
647            }
648            // String: viewport multiple like "2x" or "1.5x".
649            None => match value.as_str() {
650                Some(s) => {
651                    let lower = s.trim().to_lowercase();
652                    if lower.ends_with('x') {
653                        let num = lower.strip_suffix("x");
654                        if let Some(num) = num {
655                            if let Ok(m) = num.parse::<f64>() {
656                                if m > 0.0 {
657                                    return Ok(Some(ScreenshotHeight::ViewportTimes(m)));
658                                }
659                            }
660                        }
661                    }
662                    Err(serde::de::Error::custom(format_args!(
663                        "screenshot_max_height must be a pixel count (e.g. 2880) or a viewport multiple like \"2x\", found {s:?}"
664                    )))
665                }
666                None => Err(serde::de::Error::custom(format_args!(
667                    "screenshot_max_height must be a pixel count (e.g. 2880) or a viewport multiple like \"2x\", found {value:?}"
668                ))),
669            },
670            Some(_) => Err(serde::de::Error::custom(format_args!(
671                "screenshot_max_height value too large (max {MAX_SCREENSHOT_HEIGHT} px)"
672            ))),
673        },
674    }
675}
676
677/// Reusable assertion definition referenced by name from `assert` steps.
678///
679/// Definitions can either reference a built-in preset via `preset`, supply a
680/// custom LLM `prompt`, or define a **custom preset** by providing both
681/// `system` and `user_template`. Custom presets support the same template
682/// variables as built-in presets: `{url}`, `{title}`, `{content}`,
683/// `{expected_text}`, `{description}`.
684#[derive(Debug, Deserialize, Clone)]
685pub struct AssertDefinition {
686    /// Unique name used to reference this definition from steps.
687    pub name: String,
688    /// Predefined assertion preset name
689    /// (e.g. `no_error_on_page`, `text_visible`).
690    #[serde(default)]
691    pub preset: Option<String>,
692    /// Custom LLM prompt for assertion evaluation.
693    #[serde(default)]
694    pub prompt: Option<String>,
695    /// System prompt for a custom preset.
696    #[serde(default)]
697    pub system: Option<String>,
698    /// User template (with `{placeholders}`) for a custom preset.
699    #[serde(default)]
700    pub user_template: Option<String>,
701    /// Text that the `text_visible` preset checks for, or the
702    /// `{expected_text}` placeholder value for custom presets.
703    #[serde(default)]
704    pub assert_text: Option<String>,
705    /// Agent endpoint to call for this assertion.
706    #[serde(default)]
707    pub agent: Option<String>,
708    /// Agent task template for this assertion.
709    #[serde(default)]
710    pub task_template: Option<String>,
711}
712
713/// A group of steps that form a single test scenario.
714#[derive(Debug, Deserialize, Clone)]
715pub struct TestGroup {
716    /// Human-readable test name.
717    pub name: String,
718    /// Override the global `start_url` for this test.
719    #[serde(default)]
720    pub start_url: Option<String>,
721    /// Override the global `auto_navigate` for this test.
722    #[serde(default)]
723    pub auto_navigate: Option<bool>,
724    /// Override the global `base_url` for this test.
725    #[serde(default)]
726    pub base_url: Option<String>,
727    /// Override the global `timeout_secs` for this test.
728    #[serde(default)]
729    pub timeout_secs: Option<u64>,
730    /// Override the global `browser_headless` for this test.
731    #[serde(default)]
732    pub browser_headless: Option<bool>,
733    /// Override the global viewport width for this test (applied via CDP
734    /// `Emulation.setDeviceMetricsOverride` before the test runs).
735    #[serde(default)]
736    pub viewport_width: Option<u32>,
737    /// Override the global viewport height for this test.
738    #[serde(default)]
739    pub viewport_height: Option<u32>,
740    /// Per-test budget override.
741    #[serde(default)]
742    pub budget: Option<BudgetDef>,
743    /// Endpoint to use for all steps in this test (can be overridden
744    /// per-step).
745    #[serde(default)]
746    pub endpoint: Option<String>,
747    /// Ordered steps to execute.
748    #[serde(default)]
749    pub steps: Vec<TestStep>,
750}
751
752/// A single step in a test. The `kind` field determines which variant is
753/// deserialized and which field constraints apply.
754#[derive(Debug, Deserialize, Clone)]
755#[serde(tag = "kind")]
756pub enum TestStep {
757    /// Navigate the browser to a URL.
758    #[serde(rename = "navigate")]
759    Navigate {
760        /// URL to navigate to (absolute, or relative to the test's
761        /// base URL).
762        url: String,
763        /// Milliseconds to wait after navigation completes.
764        #[serde(default)]
765        wait_after_ms: Option<u64>,
766    },
767
768    /// Click an element described in natural language.
769    #[serde(rename = "click")]
770    Click {
771        /// Natural language description of the element. The LLM resolves
772        /// this to a CSS selector at runtime.
773        target: String,
774        /// Explicit CSS selector override (bypasses LLM resolution).
775        #[serde(default)]
776        selector: Option<String>,
777        /// Milliseconds to wait after the click.
778        #[serde(default)]
779        wait_after_ms: Option<u64>,
780        /// Endpoint to use for LLM element targeting.
781        #[serde(default)]
782        endpoint: Option<String>,
783        /// Idempotent: when the target element is absent the step is
784        /// reported skipped instead of failed (the action was already
785        /// done / not applicable).
786        #[serde(default)]
787        idempotent: bool,
788    },
789
790    /// Type text into an input element.
791    #[serde(rename = "type")]
792    Type {
793        /// Natural language description of the target input element.
794        target: String,
795        /// Text to type into the element.
796        text: String,
797        /// Explicit CSS selector override (bypasses LLM resolution).
798        #[serde(default)]
799        selector: Option<String>,
800        /// Milliseconds to wait after typing.
801        #[serde(default)]
802        wait_after_ms: Option<u64>,
803        /// Endpoint to use for LLM element targeting.
804        #[serde(default)]
805        endpoint: Option<String>,
806        /// Idempotent: when the target element is absent the step is
807        /// reported skipped instead of failed (the action was already
808        /// done / not applicable).
809        #[serde(default)]
810        idempotent: bool,
811    },
812
813    /// Wait for an element to appear on the page.
814    #[serde(rename = "wait")]
815    Wait {
816        /// Natural language description of the element to wait for.
817        target: String,
818        /// Explicit CSS selector override (bypasses LLM resolution).
819        #[serde(default)]
820        selector: Option<String>,
821        /// Wait until the page's visible text contains this substring
822        /// (alternative to `selector`; either or both may be set — both are
823        /// required to hold when both are set).
824        #[serde(default)]
825        text: Option<String>,
826        /// Maximum milliseconds to wait (default: 10000).
827        #[serde(default)]
828        timeout_ms: Option<u64>,
829        /// Endpoint to use for LLM element targeting.
830        #[serde(default)]
831        endpoint: Option<String>,
832        /// Idempotent: when the condition never becomes true within the
833        /// timeout the step is reported skipped instead of failed (the
834        /// condition was not applicable, e.g. already-authenticated
835        /// pages in a viewport matrix).
836        #[serde(default)]
837        idempotent: bool,
838    },
839
840    /// Evaluate an assertion against the current page content.
841    #[serde(rename = "assert")]
842    Assert {
843        /// Reference to a named `[[definitions]]` entry.
844        #[serde(default)]
845        definition: Option<String>,
846        /// Inline predefined assertion preset (e.g. `no_error_on_page`).
847        #[serde(default)]
848        preset: Option<String>,
849        /// Inline custom LLM prompt for assertion evaluation.
850        #[serde(default)]
851        prompt: Option<String>,
852        /// Text that the `text_visible` preset checks for.
853        #[serde(default)]
854        assert_text: Option<String>,
855        /// Endpoint to use for this assertion's LLM call.
856        #[serde(default)]
857        endpoint: Option<String>,
858        /// Attach a screenshot of the current viewport to the assertion so
859        /// the LLM can evaluate visuals (overlaps, clipping, layout).
860        /// Requires the resolved endpoint to declare `vision = true`.
861        #[serde(default)]
862        screenshot: bool,
863    },
864
865    /// Take a screenshot of the current page.
866    #[serde(rename = "screenshot")]
867    Screenshot {
868        /// File path to save the screenshot (default: `screenshot.png`).
869        #[serde(default)]
870        path: Option<String>,
871    },
872
873    /// Call an A2A agent with a task.
874    #[serde(rename = "agent")]
875    Agent {
876        /// Name of the agent endpoint to call.
877        agent: String,
878        /// Task description / prompt for the agent.
879        task: String,
880        /// Optional definition name with a task template.
881        #[serde(default)]
882        definition: Option<String>,
883    },
884
885    /// Call an MCP server tool.
886    #[serde(rename = "mcp")]
887    Mcp {
888        /// Name of the MCP server endpoint.
889        server: String,
890        /// Tool name to invoke on the server.
891        tool: String,
892        /// Tool arguments as JSON.
893        #[serde(default)]
894        args: Option<serde_json::Value>,
895    },
896}
llm_browser_testkit/scenario.rs

llm_browser_testkit/
scenario.rs
