docs: add prompt playground documentation with setup guide and feature overview

[impoiler]

Summary

Adds comprehensive documentation for the Prompt Repository Playground feature, providing users with a complete guide to creating, testing, and versioning prompts in Bifrost's interactive workspace.

Changes

• Added new "Prompt Repository" section to documentation navigation with playground page
• Created detailed playground documentation covering core concepts (folders, prompts, sessions, versions)
• Documented the three-panel workspace layout and getting started workflow
• Included key capabilities like version control, multi-provider testing, message types, attachments, and session management
• Added 7 supporting images showing the UI and workflow
• Applied minor CSS styling fix for sidebar group line height

Type of change

• Bug fix
• Feature
• Refactor
• Documentation
• Chore/CI

Affected areas

• Core (Go)
• Transports (HTTP)
• Providers/Integrations
• Plugins
• UI (Next.js)
• Docs

How to test

Verify the documentation renders correctly and navigation works:

# Navigate to docs directory and serve locally
cd docs
# Follow your documentation framework's serve command
# Verify new "Prompt Repository" section appears in navigation
# Confirm playground.mdx page loads with all images
# Test internal links and formatting

Screenshots/Recordings

The documentation includes 7 new screenshots demonstrating:

• Prompt repository overview
• Workspace layout
• Folder creation
• Prompt creation
• Playground interface
• Version commit flow
• Session management

Breaking changes

• Yes
• No

Related issues

Documents the Prompt Repository Playground feature for user onboarding and reference.

Security considerations

Documentation only - no security implications.

Checklist

• I read docs/contributing/README.md and followed the guidelines
• I added/updated tests where appropriate
• I updated documentation where needed
• I verified builds succeed (Go and UI)
• I verified the CI pipeline passes locally if applicable

[coderabbitai]

📝 Walkthrough

Summary by CodeRabbit

• Documentation

  • Added comprehensive Prompt Repository Playground docs: overview, core concepts (Folders, Prompts, Sessions, Versions), workspace layout, getting started, UI/workflow for creating and publishing immutable prompt versions, sessions management, version control, multi-provider testing, message types, attachments, and drag-and-drop organization.
  • Added a new "Prompt Repository" navigation group linking to the Playground page.

• Style

  • Minor sidebar navigation line-height and formatting adjustments.

Walkthrough

Adds documentation for a new Prompt Repository Playground: a navigation group entry, a new playground guide page, and a small CSS adjustment to sidebar styling. No functional code or API surface changes.

Changes

Cohort / File(s)	Summary
Documentation Navigation docs/docs.json	Inserted a new "Prompt Repository" navigation group with icon "folder" linking to the playground page.
Playground Feature Guide docs/features/prompt-repository/playground.mdx	Added a new comprehensive Playground documentation page describing core concepts (Folders, Prompts, Sessions, Versions), workspace layout, workflows, and capabilities (versioning, multi-provider testing, attachments, drag-and-drop).
Styling Updates docs/style.css	Added line-height: normal rule for #sidebar-group > li > button > div and minor formatting adjustments around .nav-logo block.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

Poem

🐰 In docs I hop, a tidy trail I weave,
Folders and prompts in a bright reprieve,
Sessions kept safe, versions snug and sound,
Sidebar smoothed so navigation's found,
Hooray — the Playground's written, neat and keen!

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately summarizes the main change: adding documentation for the prompt playground feature with setup guide and feature overview, which directly matches the PR's core objective.
Description check	✅ Passed	The description comprehensively follows the template with all required sections completed: summary, changes, type (documentation), affected areas (docs), testing steps, screenshots listed, breaking changes, related issues, security considerations, and a fully checked checklist.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch 03-16-docs_prompt_repo

📝 Coding Plan

• Generate coding plan for human review comments

---

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[impoiler]

• refactor: extract CEL rule builder into reusable component and add menu portal support #2237 : 2 dependent PRs (#2234 , #2327 )
• feat: add variables support to prompt sessions and versions with database migration #2154
• feat: add variables support to prompt sessions and versions with persistence #2134
• feat: add selective message inclusion when committing prompt sessions to versions #2132
• refactor: standardize icon sizing to size-3 and refine hover styles in message views #2119
• docs: add prompt playground documentation with setup guide and feature overview #2112 👈 (View in Graphite)
• feat: improve message UI with JSON editor, smaller icons, and better scroll behavior #2094
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[CLAassistant]

All committers have signed the CLA.

[CLAassistant]

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_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[coderabbitai]

Actionable comments posted: 2

🧹 Nitpick comments (1)

docs/style.css (1)

6-7: Use a less brittle selector for sidebar text styling.

The selector #sidebar-group > li > button > div depends on Mintlify's internal DOM structure, which is not guaranteed to remain stable. Mintlify explicitly warns that styling references are "subject to change as the platform evolves." Instead, prefer Mintlify's documented selector hooks (e.g., published identifiers like sidebar-group-header) or semantic data-attributes (e.g., data-component) for long-term compatibility. Verify the current Mintlify theme's rendered HTML via DevTools to identify the recommended stable hooks.

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@docs/style.css` around lines 6 - 7, The selector "#sidebar-group > li >
button > div" is brittle; inspect the Mintlify theme in DevTools to find the
documented stable hook (e.g., the published identifier like
"sidebar-group-header" or a semantic data-attribute such as
data-component="sidebar-group-header"), then replace the fragile selector in
docs/style.css with the stable hook selector (target the same element that needs
line-height: normal using the identified class or data-attribute) so styling
relies on Mintlify's supported DOM hooks rather than the internal child
structure.

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Inline comments:
In `@docs/features/prompt-repository/playground.mdx`:
- Around line 49-53: Choose one canonical keyboard shortcut for the Save Session
vs Run actions and make the docs consistent: keep the existing "Cmd + S / Ctrl +
S" mapping for either the "Save Session" entry or the "Run" entry, then update
the other occurrence to a different, unconflicting shortcut (e.g., "Cmd + Enter
/ Ctrl + Enter") and update both instances of that action's text so "Save
Session" and "Run" no longer share the same shortcut; ensure you update both the
top-bar mention under the "Save Session" paragraph and the separate "Run"
paragraph so the file's references to "Save Session" and "Run" are consistent.
- Line 15: The sentence "The playground is built around four core concepts:
**Prompts, Sessions, and Versions**." misstates the count; update that line to
either include Folders in the list or change "four" to "three". Specifically,
edit the sentence string to read either "The playground is built around four
core concepts: **Prompts, Sessions, Versions, and Folders**." or "The playground
is built around three core concepts: **Prompts, Sessions, and Versions**." so
the numeric count matches the listed items.

---

Nitpick comments:
In `@docs/style.css`:
- Around line 6-7: The selector "#sidebar-group > li > button > div" is brittle;
inspect the Mintlify theme in DevTools to find the documented stable hook (e.g.,
the published identifier like "sidebar-group-header" or a semantic
data-attribute such as data-component="sidebar-group-header"), then replace the
fragile selector in docs/style.css with the stable hook selector (target the
same element that needs line-height: normal using the identified class or
data-attribute) so styling relies on Mintlify's supported DOM hooks rather than
the internal child structure.

🪄 Autofix (Beta)

Fix all unresolved CodeRabbit comments on this PR:

• Push a commit to this branch (recommended)
• Create a new PR with the fixes

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: c1888217-c7bd-4608-b973-0f06c666216e

📥 Commits

Reviewing files that changed from the base of the PR and between 06cefd4 and e4be9d9.

⛔ Files ignored due to path filters (7)

• docs/media/prompt-repo-commit.png is excluded by !**/*.png
• docs/media/prompt-repo-create-folder.png is excluded by !**/*.png
• docs/media/prompt-repo-create-prompt.png is excluded by !**/*.png
• docs/media/prompt-repo-layout.png is excluded by !**/*.png
• docs/media/prompt-repo-overview.png is excluded by !**/*.png
• docs/media/prompt-repo-playground.png is excluded by !**/*.png
• docs/media/prompt-repo-sessions.png is excluded by !**/*.png

📒 Files selected for processing (3)

• docs/docs.json
• docs/features/prompt-repository/playground.mdx
• docs/style.css

[coderabbitai]

🧹 Nitpick comments (1)

docs/features/prompt-repository/playground.mdx (1)

131-137: Minor: Capitalize "Enter" in keyboard shortcut for consistency.

Keyboard shortcuts typically use title case. Line 53 uses Cmd + S (uppercase), but here "enter" is lowercase.

✏️ Suggested fix

-Click **Run** or press `Cmd + enter` / `Ctrl + enter`.
+Click **Run** or press `Cmd + Enter` / `Ctrl + Enter`.

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@docs/features/prompt-repository/playground.mdx` around lines 131 - 137,
Update the keyboard shortcut casing in the "Run the prompt" Step: change the
inline text from `Cmd + enter` / `Ctrl + enter` to `Cmd + Enter` / `Ctrl +
Enter` so it matches title-case usage elsewhere (e.g., `Cmd + S`) and maintains
consistency in the Step titled "Run the prompt".

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Nitpick comments:
In `@docs/features/prompt-repository/playground.mdx`:
- Around line 131-137: Update the keyboard shortcut casing in the "Run the
prompt" Step: change the inline text from `Cmd + enter` / `Ctrl + enter` to `Cmd
+ Enter` / `Ctrl + Enter` so it matches title-case usage elsewhere (e.g., `Cmd +
S`) and maintains consistency in the Step titled "Run the prompt".

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: c76a135e-0876-459a-a9e9-cb148fffe286

📥 Commits

Reviewing files that changed from the base of the PR and between e4be9d9 and e4300ea.

⛔ Files ignored due to path filters (7)

• docs/media/prompt-repo-commit.png is excluded by !**/*.png
• docs/media/prompt-repo-create-folder.png is excluded by !**/*.png
• docs/media/prompt-repo-create-prompt.png is excluded by !**/*.png
• docs/media/prompt-repo-layout.png is excluded by !**/*.png
• docs/media/prompt-repo-overview.png is excluded by !**/*.png
• docs/media/prompt-repo-playground.png is excluded by !**/*.png
• docs/media/prompt-repo-sessions.png is excluded by !**/*.png

📒 Files selected for processing (3)

• docs/docs.json
• docs/features/prompt-repository/playground.mdx
• docs/style.css

🚧 Files skipped from review as they are similar to previous changes (1)

• docs/style.css

[akshaydeo]

Merge activity

• Mar 17, 12:54 PM UTC: A user started a stack merge that includes this pull request via Graphite.
• Mar 17, 12:54 PM UTC: @akshaydeo merged this pull request with Graphite.