docs: update documentation for contract-validator (Sprint 2)

- CHANGELOG.md: Add Sprint 2 completion notes in [Unreleased]
- README.md: Add contract-validator plugin section
- docs/CANONICAL-PATHS.md: Add contract-validator paths
- docs/COMMANDS-CHEATSHEET.md: Add contract-validator commands

Preparing for v5.0.0 release.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

CHANGELOG.md

@@ -8,6 +8,32 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ### Added
 
+#### Sprint 2: contract-validator Plugin ✅ Completed
+- **contract-validator** v1.0.0 - Cross-plugin compatibility validation and CLAUDE.md agent verification
+  - **Parse Tools** (2 tools): `parse_plugin_interface`, `parse_claude_md_agents`
+    - Extracts commands, agents, tools from plugin README.md files
+    - Parses CLAUDE.md Four-Agent Model tables and Agents sections
+  - **Validation Tools** (3 tools): `validate_compatibility`, `validate_agent_refs`, `validate_data_flow`
+    - Pairwise plugin compatibility checks for command/tool conflicts
+    - Agent tool reference validation against available plugins
+    - Data flow validation for producer/consumer sequences
+  - **Report Tools** (2 tools): `generate_compatibility_report`, `list_issues`
+    - Full marketplace validation reports (markdown or JSON)
+    - Filtered issue listing by severity or type
+  - **Commands**: `/validate-contracts`, `/check-agent`, `/list-interfaces`
+  - **Agents**: `full-validation`, `agent-check`
+  - **Tests**: 34 tests passing
+    - parse_tools.py: 79% coverage
+    - validation_tools.py: 96% coverage
+    - report_tools.py: 89% coverage
+
+**Sprint Completed:**
+- Milestone: Sprint 2 - contract-validator Plugin (closed 2026-01-26)
+- Issues: #185-#193 (9/9 closed)
+- Real issue discovered: `/initial-setup` command conflict between projman, data-platform, and pr-review
+
+---
+
 #### Sprint 1: viz-platform Plugin ✅ Completed
 - **viz-platform** v1.0.0 - Visualization tools with Dash Mantine Components validation and theming
   - **DMC Tools** (3 tools): `list_components`, `get_component_props`, `validate_component`

README.md

@@ -127,6 +127,21 @@ Visualization toolkit with version-locked component validation and design token
 
 **Commands:** `/chart`, `/dashboard`, `/theme`, `/theme-new`, `/theme-css`, `/component`, `/initial-setup`
 
+### Validation
+
+#### [contract-validator](./plugins/contract-validator/README.md) *NEW*
+**Cross-Plugin Compatibility Validation**
+
+Validates plugin interfaces and CLAUDE.md agent definitions for compatibility issues.
+
+- 2 Parse tools for extracting interfaces from README.md and CLAUDE.md
+- 3 Validation tools for compatibility checks and data flow verification
+- 2 Report tools for comprehensive marketplace reports
+- Detects command conflicts, tool overlaps, and missing references
+- 34 tests with 88% average coverage
+
+**Commands:** `/validate-contracts`, `/check-agent`, `/list-interfaces`
+
 ## MCP Servers
 
 MCP servers are **shared at repository root** with **symlinks** from plugins that use them.

docs/CANONICAL-PATHS.md

@@ -2,7 +2,7 @@
 
 **This file defines ALL valid paths in this repository. No exceptions. No inference. No assumptions.**
 
-Last Updated: 2026-01-26 (v4.1.0)
+Last Updated: 2026-01-26 (v5.0.0)
 
 ---
 
@@ -49,19 +49,28 @@ leo-claude-mktplace/
 │   │   │   └── dbt_tools.py
 │   │   ├── requirements.txt
 │   │   └── .venv/
-│   └── viz-platform/           # Visualization MCP (NEW v4.1.0)
+│   ├── viz-platform/           # Visualization MCP (NEW v4.1.0)
+│   │   ├── mcp_server/
+│   │   │   ├── server.py
+│   │   │   ├── config.py
+│   │   │   ├── component_registry.py
+│   │   │   ├── dmc_tools.py
+│   │   │   ├── chart_tools.py
+│   │   │   ├── layout_tools.py
+│   │   │   ├── theme_tools.py
+│   │   │   ├── theme_store.py
+│   │   │   └── page_tools.py
+│   │   ├── registry/           # DMC component JSON registries
+│   │   ├── tests/              # 94 tests
+│   │   ├── requirements.txt
+│   │   └── .venv/
+│   └── contract-validator/     # Validation MCP (NEW v5.0.0)
 │       ├── mcp_server/
 │       │   ├── server.py
-│       │   ├── config.py
+│       │   ├── parse_tools.py
-│       │   ├── component_registry.py
+│       │   ├── validation_tools.py
-│       │   ├── dmc_tools.py
+│       │   └── report_tools.py
-│       │   ├── chart_tools.py
+│       ├── tests/              # 34 tests
-│       │   ├── layout_tools.py
-│       │   ├── theme_tools.py
-│       │   ├── theme_store.py
-│       │   └── page_tools.py
-│       ├── registry/           # DMC component JSON registries
-│       ├── tests/              # 94 tests
 │       ├── requirements.txt
 │       └── .venv/
 ├── plugins/                    # ALL plugins
@@ -135,14 +144,22 @@ leo-claude-mktplace/
 │   │   ├── agents/
 │   │   ├── hooks/
 │   │   └── claude-md-integration.md
-│   └── viz-platform/           # NEW in v4.1.0
+│   ├── viz-platform/           # NEW in v4.1.0
+│   │   ├── .claude-plugin/
+│   │   ├── .mcp.json
+│   │   ├── mcp-servers/
+│   │   │   └── viz-platform -> ../../../mcp-servers/viz-platform  # SYMLINK
+│   │   ├── commands/
+│   │   ├── agents/
+│   │   ├── hooks/
+│   │   └── claude-md-integration.md
+│   └── contract-validator/     # NEW in v5.0.0
 │       ├── .claude-plugin/
 │       ├── .mcp.json
 │       ├── mcp-servers/
-│       │   └── viz-platform -> ../../../mcp-servers/viz-platform  # SYMLINK
+│       │   └── contract-validator -> ../../../mcp-servers/contract-validator  # SYMLINK
 │       ├── commands/
 │       ├── agents/
-│       ├── hooks/
 │       └── claude-md-integration.md
 ├── scripts/                    # Setup and maintenance scripts
 │   ├── setup.sh                # Initial setup (create venvs, config templates)
@@ -269,6 +286,7 @@ plugins/cmdb-assistant/mcp-servers/netbox -> ../../../mcp-servers/netbox
 plugins/pr-review/mcp-servers/gitea -> ../../../mcp-servers/gitea
 plugins/data-platform/mcp-servers/data-platform -> ../../../mcp-servers/data-platform
 plugins/viz-platform/mcp-servers/viz-platform -> ../../../mcp-servers/viz-platform
+plugins/contract-validator/mcp-servers/contract-validator -> ../../../mcp-servers/contract-validator
 ```
 
 ---
@@ -277,6 +295,7 @@ plugins/viz-platform/mcp-servers/viz-platform -> ../../../mcp-servers/viz-platfo
 
 | Date | Change | By |
 |------|--------|-----|
+| 2026-01-26 | v5.0.0: Added contract-validator plugin and MCP server | Claude Code |
 | 2026-01-26 | v4.1.0: Added viz-platform plugin and MCP server | Claude Code |
 | 2026-01-25 | v4.0.0: Added data-platform plugin and MCP server | Claude Code |
 | 2026-01-20 | v3.0.0: MCP servers moved to root with symlinks | Claude Code |

docs/COMMANDS-CHEATSHEET.md

@@ -72,6 +72,9 @@ Quick reference for all commands in the Leo Claude Marketplace.
 | **viz-platform** | `/theme-css` | | X | Export theme as CSS custom properties |
 | **viz-platform** | `/component` | | X | Inspect DMC component props and validation |
 | **viz-platform** | *SessionStart hook* | X | | Checks DMC version (non-blocking warning) |
+| **contract-validator** | `/validate-contracts` | | X | Full marketplace cross-plugin compatibility validation |
+| **contract-validator** | `/check-agent` | | X | Validate single agent definition and tool references |
+| **contract-validator** | `/list-interfaces` | | X | Show all plugin interfaces (commands, agents, tools) |
 
 ---
 
@@ -87,6 +90,7 @@ Quick reference for all commands in the Leo Claude Marketplace.
 | **Infrastructure** | cmdb-assistant | NetBox CMDB management |
 | **Data Engineering** | data-platform | pandas, PostgreSQL, dbt operations |
 | **Visualization** | viz-platform | DMC validation, Plotly charts, theming |
+| **Validation** | contract-validator | Cross-plugin compatibility validation |
 | **Maintenance** | project-hygiene | Automatic cleanup |
 
 ---
@@ -245,9 +249,10 @@ Some plugins require MCP server connectivity:
 | cmdb-assistant | NetBox | Infrastructure CMDB |
 | data-platform | pandas, PostgreSQL, dbt | DataFrames, database queries, dbt builds |
 | viz-platform | viz-platform | DMC validation, charts, layouts, themes, pages |
+| contract-validator | contract-validator | Plugin parsing, compatibility validation, reports |
 
 Ensure credentials are configured in `~/.config/claude/gitea.env`, `~/.config/claude/netbox.env`, or `~/.config/claude/postgres.env`.
 
 ---
 
-*Last Updated: 2026-01-26*
+*Last Updated: 2026-01-26 (v5.0.0)*