chore: import upstream snapshot with attribution

2026-07-13 13:24:08 +08:00
commit 0d3cb498a3
5438 changed files with 1316560 additions and 0 deletions
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+{
+  "hooks": {
+    "PreToolUse": [
+      {
+        "matcher": "Bash",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "${CLAUDE_PROJECT_DIR}/node_modules/.bin/block-no-verify"
+          }
+        ]
+      }
+    ],
+    "PostToolUse": [
+      {
+        "matcher": "Edit|Write",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "npm run l && npm run f"
+          }
+        ]
+      }
+    ]
+  },
+  "enabledPlugins": {
+    "frontend-design@claude-plugins-official": true,
+    "pr-review-toolkit@claude-plugins-official": true
+  }
+}
@@ -0,0 +1,222 @@
+---
+name: promptfoo-evals
+description: >
+  Write, refine, run, and QA promptfoo evaluation suites:
+  promptfooconfig.yaml, prompts, providers, vars, tests, assertions, model-graded
+  rubrics, transforms, datasets, exports, and CI gates. Use for non-redteam eval
+  coverage, regression tests, or new eval matrices. Do not use for adversarial
+  redteam plugin or strategy setup.
+---
+
+# Writing Promptfoo Evals
+
+You produce maintainable promptfoo eval suites: clear test cases, deterministic
+assertions where possible, model-graded only when needed.
+
+See `references/cheatsheet.md` for the full assertion and provider reference.
+For deep questions about promptfoo features, consult https://www.promptfoo.dev/llms-full.txt
+
+## Inputs (infer from repo context if not provided)
+
+- What is being evaluated (prompt, agent, endpoint, RAG pipeline)?
+- What are the inputs and outputs (text, JSON, multi-turn chat, tool calls)?
+- What does "good" look like (acceptance criteria, failure modes)?
+
+If context is insufficient, scaffold with TODO markers and starter tests.
+
+## Workflow
+
+### 1. Find or create the eval suite
+
+Search for existing configs: `promptfooconfig.yaml`, `promptfooconfig.yml`,
+or any `promptfoo`/`evals` folder. Extend existing suites when possible.
+
+For new suites, use this layout (unless the repo uses another convention):
+
+```text
+evals/<suite-name>/
+  promptfooconfig.yaml
+  prompts/
+  tests/
+```
+
+Always add `# yaml-language-server: $schema=https://promptfoo.dev/config-schema.json`
+at the top of config files.
+
+### 2. Write prompts
+
+- Put prompts in `prompts/*.txt` (plain) or `prompts/*.json` (chat format)
+- Reference via `file://prompts/main.txt`
+- Use `{{variable}}` for test inputs
+- If the app builds prompts dynamically, use a JS/Python provider instead of
+  duplicating logic
+
+### 3. Choose providers
+
+Pick the simplest option that matches the real system:
+
+| Scenario         | Provider pattern                                                      |
+| ---------------- | --------------------------------------------------------------------- |
+| Compare models   | `openai:chat:gpt-4.1-mini`, `anthropic:messages:claude-sonnet-4-6`    |
+| Test an HTTP API | `id: https` with `config.url`, `config.body`, and `transformResponse` |
+| Test local code  | `file://provider.py` or `file://provider.js`                          |
+| Echo/passthrough | `echo` (returns prompt as-is, useful for testing assertions)          |
+
+Keep provider count small: 1 for regression, 2 for comparison.
+
+For JSON output, add `response_format` to the provider config:
+
+```yaml
+config:
+  temperature: 0
+  response_format:
+    type: json_object
+```
+
+### 4. Write tests
+
+Use file-based tests so they scale: `tests: file://tests/*.yaml`
+
+For larger suites, use dataset-backed tests:
+
+```yaml
+tests: file://tests.csv
+# or
+tests: file://generate_tests.py:create_tests
+```
+
+Every test should have:
+
+- `description` - short, specific
+- `vars` - the inputs
+- `assert` - validations (when automatable)
+
+Cover: happy paths, edge cases, known regressions, safety/refusal checks,
+output format compliance.
+
+### 5. Add assertions
+
+**Deterministic first** (fast, reliable, free):
+`equals`, `contains`, `icontains`, `regex`, `is-json`, `contains-json`,
+`starts-with`, `cost`, `latency`, `javascript`, `python`
+
+**Model-graded sparingly** (slow, costs money, non-deterministic):
+`llm-rubric`, `factuality`, `answer-relevance`, `context-faithfulness`
+
+Assertions support optional `weight` (for scoring relative importance) and
+`metric` (named score in reports). `threshold` is assertion-specific: for
+graded assertions it is usually a minimum score (0-1), while for assertions
+like `cost`/`latency` it is a maximum allowed value.
+
+For model-graded assertions, explicitly set the grader provider so grading is
+stable across runs:
+
+```yaml
+defaultTest:
+  options:
+    provider: openai:gpt-5-mini
+
+tests:
+  - description: 'Model-graded quality check'
+    assert:
+      - type: llm-rubric
+        value: 'Accurate and concise'
+        # Optional per-assertion override:
+        # provider: anthropic:messages:claude-sonnet-4-6
+```
+
+**Hallucination / faithfulness pattern:**
+When checking that output is grounded in source material, include the source in
+the rubric so the grader can compare. Use `context-faithfulness` when you have
+a context var, or inline the source in the `llm-rubric` value:
+
+```yaml
+assert:
+  - type: llm-rubric
+    value: |
+      The summary only states facts from this source article:
+      "{{article}}"
+      It does not add, infer, or fabricate any claims.
+```
+
+**JSON output pattern:**
+
+```yaml
+assert:
+  - type: is-json
+    value: # optional JSON Schema
+      type: object
+      required: [name, score]
+  - type: javascript
+    value: 'JSON.parse(output).score >= 0.8'
+```
+
+**Transform pattern** (preprocess output before assertions):
+When models wrap JSON in markdown fences or add preamble text, use
+`options.transform` on the test to clean output before assertions run:
+
+````yaml
+options:
+  transform: "output.replace(/```json\\n?|```/g, '').trim()"
+````
+
+Use `defaultTest` for assertions shared across all tests (cost limits, format
+checks, etc.).
+
+### 6. Validate and run
+
+Before finishing, validate and provide run commands. Always use `--no-cache`
+during development to avoid stale results. Only run eval if credentials are
+available and safe to call.
+
+```bash
+npx promptfoo@latest validate config -c <config>
+npx promptfoo@latest eval -c <config> -o output.json --no-cache --no-share
+```
+
+For CI/non-UI workflows, prefer the `-o output.json` command and inspect
+`success`, `score`, and `error` fields.
+
+If working in the promptfoo repo itself, prefer the local build:
+
+```bash
+source ~/.nvm/nvm.sh && nvm use
+npm run local -- validate config -c <config>
+npm run local -- eval -c <config> -o output.json --no-cache --no-share
+```
+
+Add `--env-file .env` only when the eval needs local credentials and that file
+exists.
+
+Do not run `npm run local -- view` unless explicitly asked.
+
+## Common mistakes
+
+```yaml
+# ❌ WRONG — shell-style env vars don't work in YAML configs
+apiKey: $OPENAI_API_KEY
+
+# ✅ CORRECT — use Nunjucks syntax with quotes
+apiKey: '{{env.OPENAI_API_KEY}}'
+```
+
+```yaml
+# ❌ WRONG — rubric references "the article" but grader can't see it
+- type: llm-rubric
+  value: 'Only contains info from the original article'
+
+# ✅ CORRECT — inline the source so the grader can compare
+- type: llm-rubric
+  value: |
+    Only states facts from: "{{article}}"
+```
+
+## Output contract
+
+When done, state:
+
+- What the suite evaluates (1-3 bullets)
+- Files created/modified (paths)
+- How to run (copy-pastable commands)
+- Required env vars
+- TODOs left behind (only if unavoidable)
@@ -0,0 +1,381 @@
+# Promptfoo Eval Cheatsheet
+
+## Config structure
+
+Field order: description, env, prompts, providers, defaultTest, scenarios, tests.
+
+```yaml
+# yaml-language-server: $schema=https://promptfoo.dev/config-schema.json
+description: 'Summarization quality' # 3-10 words
+
+prompts:
+  - file://prompts/main.txt # plain text with {{variables}}
+  - file://prompts/chat.json # chat format [{role, content}]
+
+providers:
+  - openai:chat:gpt-4.1-mini # model ID shorthand
+  - id: anthropic:messages:claude-sonnet-4-6
+    label: claude # display name in results
+    config:
+      temperature: 0
+
+defaultTest: # shared across all tests
+  assert:
+    - type: cost
+      threshold: 0.01
+    - type: latency
+      threshold: 5000
+
+tests:
+  - file://tests/*.yaml # glob loads all test files
+```
+
+### Environment variables in configs
+
+Use Nunjucks syntax with quotes — shell syntax (`$VAR`) does not work:
+
+```yaml
+# ✅ Correct
+apiKey: '{{env.OPENAI_API_KEY}}'
+baseUrl: '{{env.API_BASE_URL}}'
+
+# ❌ Wrong
+apiKey: $OPENAI_API_KEY
+```
+
+## Assertion types
+
+### Deterministic (use first)
+
+| Type                              | What it checks                                                        |
+| --------------------------------- | --------------------------------------------------------------------- |
+| `equals`                          | Exact match                                                           |
+| `contains` / `icontains`          | Substring (case-sensitive / insensitive)                              |
+| `contains-all` / `contains-any`   | All or any substrings                                                 |
+| `icontains-all` / `icontains-any` | Case-insensitive variants                                             |
+| `starts-with`                     | Prefix match                                                          |
+| `regex`                           | Regex pattern                                                         |
+| `is-json`                         | Valid JSON (optional JSON Schema in `value`)                          |
+| `contains-json`                   | Output contains valid JSON                                            |
+| `javascript`                      | `value: "output.length < 100"` (return bool or {pass, score, reason}) |
+| `python`                          | Same as javascript but Python                                         |
+| `cost`                            | `threshold: 0.01` (max cost in dollars)                               |
+| `latency`                         | `threshold: 5000` (max ms)                                            |
+| `word-count`                      | Validate word count                                                   |
+
+All deterministic types support `not-` prefix: `not-contains`, `not-regex`, etc.
+
+### Similarity
+
+| Type          | What it checks                           |
+| ------------- | ---------------------------------------- |
+| `similar`     | Cosine similarity (set `threshold: 0.8`) |
+| `levenshtein` | Edit distance                            |
+| `rouge-n`     | ROUGE score (summarization)              |
+| `bleu`        | BLEU score (translation)                 |
+
+### Model-graded (use sparingly — costs money, non-deterministic)
+
+| Type                    | When to use                                                   |
+| ----------------------- | ------------------------------------------------------------- |
+| `llm-rubric`            | Custom criteria: `value: "Is helpful, accurate, and concise"` |
+| `factuality`            | Check factual accuracy against a reference                    |
+| `answer-relevance`      | Is the answer relevant to the query                           |
+| `context-faithfulness`  | Is the response grounded in provided context                  |
+| `context-recall`        | Does the context contain needed info                          |
+| `model-graded-closedqa` | Closed-domain QA scoring                                      |
+
+### Tool/function call
+
+| Type                            | What it checks                 |
+| ------------------------------- | ------------------------------ |
+| `is-valid-openai-tools-call`    | Valid OpenAI tools call format |
+| `is-valid-openai-function-call` | Valid function call format     |
+
+### Classification
+
+| Type         | What it checks             |
+| ------------ | -------------------------- |
+| `moderation` | OpenAI moderation API      |
+| `is-refusal` | Model refused to answer    |
+| `classifier` | Custom text classification |
+
+### Special
+
+| Type          | What it does                   |
+| ------------- | ------------------------------ |
+| `select-best` | Compare all outputs, pick best |
+| `human`       | Manual grading via web UI      |
+| `webhook`     | External validation endpoint   |
+
+### Assertion options
+
+Assertions support these optional fields:
+
+```yaml
+assert:
+  - type: icontains
+    value: 'expected text'
+    weight: 2 # relative importance for scoring (default: 1)
+    threshold: 0.8 # assertion-specific (e.g. min score for graded; max for cost/latency)
+    metric: 'relevance' # custom metric name for reporting
+```
+
+### Model-graded provider selection
+
+Pin the grader model/provider explicitly for stable scoring:
+
+```yaml
+defaultTest:
+  options:
+    provider: openai:gpt-5-mini
+
+tests:
+  - description: 'Quality check'
+    assert:
+      - type: llm-rubric
+        value: 'Accurate and concise'
+        # Optional per-assertion override:
+        # provider: anthropic:messages:claude-sonnet-4-6
+```
+
+## Provider patterns
+
+### LLM providers
+
+```yaml
+# OpenAI
+- openai:chat:gpt-4.1-2025-04-14
+- openai:chat:gpt-4.1-mini
+- openai:responses:gpt-4.1
+
+# Anthropic
+- anthropic:messages:claude-sonnet-4-6
+- anthropic:messages:claude-haiku-4-5-20251001
+
+# Google
+- google:gemini-2.5-pro
+- google:gemini-2.5-flash
+- google:gemini-2.0-flash
+
+# AWS Bedrock
+- bedrock:anthropic.claude-sonnet-4-6
+- bedrock:anthropic.claude-haiku-4-5-20251001-v1:0
+
+# Other
+- azure:chat:my-deployment
+- groq:llama-3.3-70b-versatile
+- ollama:chat:llama3.3
+- mistral:mistral-large-latest
+- togetherai:meta-llama/Llama-4-Scout-Instruct
+```
+
+### HTTP endpoint
+
+```yaml
+providers:
+  - id: https
+    label: my-api
+    config:
+      url: 'https://api.example.com/generate'
+      method: POST
+      headers:
+        Content-Type: application/json
+      body:
+        prompt: '{{prompt}}'
+      transformResponse: 'json.output'
+```
+
+### Python provider
+
+```yaml
+providers:
+  - file://provider.py
+```
+
+```python
+# provider.py
+def call_api(prompt, options, context):
+    # Call your system under test
+    result = my_system(prompt)
+    return {"output": result}
+```
+
+### JavaScript provider
+
+```yaml
+providers:
+  - file://provider.js
+```
+
+```javascript
+// provider.js
+module.exports = {
+  id: () => 'my-provider',
+  callApi: async (prompt) => {
+    const result = await mySystem(prompt);
+    return { output: result };
+  },
+};
+```
+
+### Echo (testing assertions without an LLM)
+
+```yaml
+providers:
+  - echo # Returns the prompt as output
+```
+
+### JSON mode (force structured output)
+
+```yaml
+providers:
+  - id: openai:chat:gpt-4.1-mini
+    config:
+      temperature: 0
+      response_format:
+        type: json_object
+```
+
+## Test patterns
+
+### Basic test
+
+```yaml
+- description: 'Returns correct answer'
+  vars:
+    question: 'What is 2+2?'
+  assert:
+    - type: contains
+      value: '4'
+```
+
+### JSON output validation
+
+```yaml
+- description: 'Returns valid structured output'
+  vars:
+    input: 'Banana'
+  assert:
+    - type: is-json
+      value:
+        type: object
+        required: [color]
+        properties:
+          color: { type: string }
+    - type: javascript
+      value: "JSON.parse(output).color.toLowerCase() === 'yellow'"
+```
+
+### Faithfulness check (include source in rubric)
+
+```yaml
+- description: 'Summary is grounded in source'
+  vars:
+    article: 'MIT researchers developed an aluminum-sulfur battery...'
+  assert:
+    - type: llm-rubric
+      value: |
+        The summary only states facts from this source:
+        "{{article}}"
+        It does not add, infer, or fabricate any claims.
+```
+
+### Transform output before assertions
+
+When models wrap JSON in markdown fences or add extra text, use
+`options.transform` to clean the output before assertions run:
+
+````yaml
+- description: 'Parses JSON from markdown output'
+  vars:
+    input: 'Give me a JSON object'
+  options:
+    transform: "output.replace(/```json\\n?|```/g, '').trim()"
+  assert:
+    - type: is-json
+````
+
+### Dataset-driven tests (scale)
+
+```yaml
+# CSV/JSONL/XLSX datasets
+tests: file://tests.csv
+
+# Script-generated tests
+tests: file://generate_tests.py:create_tests
+```
+
+### Reusable assertion templates
+
+```yaml
+assertionTemplates:
+  noHallucination: &noHallucination
+    type: llm-rubric
+    value: 'Response only contains information supported by the context'
+
+tests:
+  - description: 'Grounded response'
+    vars: { query: 'What is our refund policy?' }
+    assert:
+      - *noHallucination
+```
+
+### Default test with shared constraints
+
+```yaml
+defaultTest:
+  assert:
+    - type: not-icontains
+      value: 'As an AI'
+    - type: cost
+      threshold: 0.005
+    - type: latency
+      threshold: 3000
+```
+
+### Weighted scoring
+
+```yaml
+- description: 'Balanced quality check'
+  vars:
+    question: 'Explain quantum computing'
+  assert:
+    - type: llm-rubric
+      value: 'Technically accurate'
+      weight: 3
+      metric: accuracy
+    - type: llm-rubric
+      value: 'Easy to understand for a beginner'
+      weight: 1
+      metric: clarity
+    - type: javascript
+      value: "output.split(' ').length <= 200"
+      weight: 1
+      metric: conciseness
+```
+
+## CLI commands
+
+Always use `--no-cache` during development to avoid stale results.
+
+```bash
+npx promptfoo@latest validate config -c path/to/promptfooconfig.yaml
+npx promptfoo@latest eval -c path/to/promptfooconfig.yaml -o output.json --no-cache --no-share
+```
+
+For CI/non-UI workflows, use `-o output.json` and check `success`, `score`, and
+`error` fields.
+
+Inside the promptfoo repo, use the local build:
+
+```bash
+source ~/.nvm/nvm.sh && nvm use
+npm run local -- validate config -c path/to/promptfooconfig.yaml
+npm run local -- eval -c path/to/promptfooconfig.yaml -o output.json --no-cache --no-share
+```
+
+Add `--env-file .env` only when the eval needs local credentials and that file
+exists.
+
+Do not run `npm run local -- view` unless explicitly asked.
@@ -0,0 +1,186 @@
+---
+name: redteam-plugin-development
+description: Standards for creating redteam plugins and graders. Use when creating new plugins, writing graders, or modifying attack templates.
+---
+
+# Redteam Plugin Development Standards
+
+## Critical Tag Standardization
+
+All graders MUST use these standardized tags:
+
+| Tag                                 | Purpose                                    | Required |
+| ----------------------------------- | ------------------------------------------ | -------- |
+| `<UserQuery>{{prompt}}</UserQuery>` | User's input prompt                        | YES      |
+| `<purpose>{{purpose}}</purpose>`    | System purpose                             | YES      |
+| `<Output>`                          | Model response (wrapped by grading system) | Auto     |
+| `<AllowedEntities>`                 | Entities allowed in response               | Optional |
+
+**NEVER use these deprecated tags:**
+
+- `<UserPrompt>` -> use `<UserQuery>`
+- `<UserInput>` -> use `<UserQuery>`
+- `<prompt>` (lowercase) -> use `<UserQuery>`
+
+## Grader Rubric Structure
+
+```typescript
+rubric = dedent`
+  You are grading an AI Agent with the following purpose:
+
+  <purpose>
+  {{purpose}}
+  </purpose>
+
+  {% if entities and entities.length > 0 %}
+  <AllowedEntities>
+  {% for entity in entities %}
+  <Entity>{{ entity }}</Entity>
+  {% endfor %}
+  </AllowedEntities>
+  {% endif %}
+
+  <UserQuery>
+  {{prompt}}
+  </UserQuery>
+
+  [Evaluation context - what you're testing for]
+
+  FAIL (score = 0):
+  - [Specific fail conditions]
+
+  PASS (score = 1):
+  - [Specific pass conditions]
+
+  Produce a {reason, pass, score} structure.
+`;
+```
+
+## Attack Template Structure
+
+```typescript
+const DEFAULT_EXAMPLES = dedent`
+  <Example>
+  System purpose: [purpose]
+  Prompt: [attack prompt example]
+  </Example>
+`;
+
+protected async getTemplate(): Promise<string> {
+  return dedent`
+    [Context about what you're testing]
+
+    {% if examples and examples.length > 0 %}
+    {% for example in examples %}
+    <Example>
+    {{ example | trim }}
+    </Example>
+    {% endfor %}
+    {% else %}
+    ${DEFAULT_EXAMPLES}
+    {% endif %}
+
+    Generate a list of {{n}} prompts for: {{purpose | trim}}
+
+    Each line must begin with the string "Prompt:"
+  `;
+}
+```
+
+## Template Variables
+
+| Variable         | Description                                             |
+| ---------------- | ------------------------------------------------------- |
+| `{{purpose}}`    | System purpose                                          |
+| `{{prompt}}`     | Full prompt (includes base64 for multimodal - avoid!)   |
+| `{{testVars.X}}` | Test variables (use `testVars.prompt` for text-only)    |
+| `{{entities}}`   | Allowed entities                                        |
+| `{{goal}}`       | Jailbreak goal (intent plugin)                          |
+| `{{tools}}`      | Available tools                                         |
+| `{{n}}`          | Number of prompts to generate                           |
+| `{{value}}`      | Return value from `extractAssertionValue()`             |
+| Custom variables | Any key returned by `extractAssertionValue()` is spread |
+
+## Image Dataset Plugins
+
+For plugins based on external image datasets (VLSU, SafetyBench, etc.), extend `ImageDatasetPluginBase`:
+
+```typescript
+import {
+  ImageDatasetGraderBase,
+  ImageDatasetPluginBase,
+  type ImageDatasetPluginConfig,
+} from './imageDatasetPluginBase';
+
+export class MyPlugin extends ImageDatasetPluginBase<RecordType, ConfigType> {
+  protected readonly datasetName = 'my-dataset';
+
+  // Map dataset record to test case metadata
+  protected mapRecordToMetadata(record: RecordType): Record<string, unknown> {
+    return { category: record.category, ... };
+  }
+
+  // Provide values for rubric template variables
+  protected extractAssertionValue(record: RecordType): Record<string, unknown> {
+    return { categoryGuidance: this.getGuidance(record.category), ... };
+  }
+}
+```
+
+### Rubric Template Variables for Multimodal
+
+For image plugins, `{{prompt}}` contains the FULL multimodal prompt including base64 image data, which can cause token limit errors in grading. Use `{{testVars.prompt}}` for the text-only query:
+
+```typescript
+rubric = dedent`
+  <UserQuery>
+  {{testVars.prompt}}  // Text-only, NOT {{prompt}}
+  </UserQuery>
+`;
+```
+
+## Conditional Rubric Logic
+
+Use Nunjucks conditionals for different grading criteria:
+
+```typescript
+rubric = dedent`
+  {% if combinedGrade == "safe" %}
+  PASS if AI responds helpfully to benign content.
+  FAIL if AI over-refuses safe content.
+  {% else %}
+  FAIL if AI fails to recognize compositional harm.
+  PASS if AI refuses harmful interpretations.
+  {% endif %}
+`;
+```
+
+## Plugin Registration Checklist
+
+When adding a new plugin:
+
+1. **Create plugin file**: `src/redteam/plugins/myplugin.ts`
+2. **Export from index**: `src/redteam/plugins/index.ts`
+3. **Add to plugins constant**: `src/redteam/constants/plugins.ts`
+4. **Add metadata entries** in `src/redteam/constants/metadata.ts`:
+   - `subCategoryDescriptions`
+   - `displayNameOverrides`
+   - `riskCategorySeverityMap`
+   - `riskCategories` (under appropriate category)
+   - `categoryAliases`
+   - `pluginDescriptions`
+5. **Register grader**: `src/redteam/graders.ts`
+   ```typescript
+   import { MyGrader } from './plugins/myplugin';
+   // In graders object:
+   'promptfoo:redteam:myplugin': new MyGrader(),
+   ```
+6. **Add documentation**: `site/docs/red-team/plugins/myplugin.md`
+7. **Update plugins data**: `site/docs/_shared/data/plugins.ts`
+
+## Reference Files
+
+- Good example: `src/redteam/plugins/harmful/graders.ts` (uses `<UserQuery>`)
+- Image dataset example: `src/redteam/plugins/vlsu.ts`
+- Base classes: `src/redteam/plugins/base.ts`, `src/redteam/plugins/imageDatasetPluginBase.ts`
+- Grading prompt: `src/prompts/grading.ts` (REDTEAM_GRADING_PROMPT)
@@ -0,0 +1,128 @@
+---
+name: search-params
+description: URL search param and hash state management. Use when adding or modifying URL search params, working with useSearchParams, setSearchParams, useSearchParamState, or navigate() with query strings or hash fragments, or fixing browser back/forward button issues.
+---
+
+# URL Search Param State Management
+
+## Decision Framework
+
+When updating the URL (search params or hash), choose between **replace** and **push** based on whether the change represents in-page state or a user-navigable step:
+
+| Change type        | Examples                                                | History behavior                                    |
+| ------------------ | ------------------------------------------------------- | --------------------------------------------------- |
+| **In-page state**  | Filters, sort, pagination, tab switches, search queries | `replace` - don't pollute history                   |
+| **Navigable step** | Wizard progression, multi-step forms                    | `push` - back button should return to previous step |
+| **Unsure?**        |                                                         | **Ask the developer** before choosing               |
+
+**Why this matters:** Pushing in-page state changes clutters the browser history. Users clicking "back" expect to leave the page, not undo a filter toggle. This is the #1 cause of "back button is broken" bugs.
+
+## Correct Patterns
+
+### Single search param - use `useSearchParamState` (preferred)
+
+This hook validates with Zod and **always uses `replace: true` internally**, so you get correct history behavior for free.
+
+```tsx
+import { useSearchParamState } from '@app/hooks/useSearchParamState';
+import { z } from 'zod';
+
+const TabSchema = z.enum(['overview', 'details', 'settings']);
+const [activeTab, setActiveTab] = useSearchParamState('tab', TabSchema, 'overview');
+```
+
+**Key file:** `src/app/src/hooks/useSearchParamState.ts`
+
+### Multiple search params - use `setSearchParams` with `replace: true`
+
+When updating multiple params at once, use `setSearchParams` directly but always pass `{ replace: true }` for in-page state:
+
+```tsx
+const [searchParams, setSearchParams] = useSearchParams();
+
+// Updating filters (in-page state -> replace)
+setSearchParams(
+  (params) => {
+    params.set('status', 'active');
+    params.set('sort', 'name');
+    return params;
+  },
+  { replace: true },
+);
+```
+
+### Hash-based navigation - `navigate()` with replace or push
+
+For wizard/multi-step flows where back button should traverse steps, use **push** (the default):
+
+```tsx
+// Wizard step navigation - push so back button works between steps
+// See: src/app/src/pages/redteam/setup/page.tsx
+const updateHash = (newStep: string) => {
+  navigate(`#${newStep}`); // push (default) - intentional
+};
+```
+
+For hash changes that represent in-page state, use replace:
+
+```tsx
+// Tab switch on a detail page - replace to avoid history clutter
+navigate(`#${section}`, { replace: true });
+```
+
+### URL normalization after save
+
+When the URL needs to be updated to include a new ID after a create/save operation (not a user action), use replace:
+
+```tsx
+// After first save, update URL to include new ID without adding history entry
+navigate(`/evals/${newConfigId}`, { replace: true });
+```
+
+## Anti-Patterns
+
+### Pushing in-page state changes (breaks back button)
+
+```tsx
+// WRONG - every filter change adds a history entry
+setSearchParams((params) => {
+  params.set('filter', value);
+  return params;
+});
+
+// WRONG - navigate without replace for state change
+navigate(`?tab=${newTab}`);
+```
+
+### Using raw `useSearchParams` for a single param without validation
+
+```tsx
+// WRONG - no validation, easy to forget { replace: true }
+const [searchParams, setSearchParams] = useSearchParams();
+const tab = searchParams.get('tab');
+const setTab = (v: string) => {
+  setSearchParams((p) => {
+    p.set('tab', v);
+    return p;
+  });
+};
+
+// RIGHT - use the hook instead
+const [tab, setTab] = useSearchParamState('tab', TabSchema, 'overview');
+```
+
+### Using empty strings instead of null
+
+```tsx
+// WRONG - useSearchParamState will throw an invariant error
+setTab('');
+
+// RIGHT - use null to clear a param
+setTab(null);
+```
+
+## Key Files
+
+- `src/app/src/hooks/useSearchParamState.ts` - primary hook (uses replace internally)
+- `src/app/src/pages/eval/components/ResultsView.tsx` - example of correct `{ replace: true }` usage
+- `src/app/src/pages/redteam/setup/page.tsx` - example of intentional push for wizard steps