# get_contract_versions Show version history for a service API contract with breaking change detection between versions. Compares request/response schemas across snapshots to flag removed fields, type changes, and renames. Use to review API evolution. For current spec-vs-code drift use get_contract_drift instead. Read-only. Returns JSON: { service, versions: [{ version, date, breakingChanges }] }. Agent View of the PolicyLayer registry record for `get_contract_versions`. HTML page: https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/get-contract-versions ## Facts - Tool: `get_contract_versions` - Server: Trace (`nikolai-vysotskyi/trace-mcp`) — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp.md - Homepage: https://github.com/nikolai-vysotskyi/trace-mcp - Risk category: Read (Low risk) - Registry record: grade F, identity unverified - Server rate-limited: no - Parameters: 0 - Recommended policy verdict: Allowed ## Example call (MCP tools/call, JSON-RPC 2.0) ```json { "jsonrpc": "2.0", "id": 1, "method": "tools/call", "params": { "name": "get_contract_versions", "arguments": {} } } ``` ## Why get_contract_versions is rated Low This tool retrieves and queries API contract version history with breaking change detection analysis. It performs no writes, deletes, executions, or financial operations. The read-only confirmation in the description and passive comparison operation definitively place this in the Read category with low severity since it only surfaces historical metadata about API contracts. From the tool's own definition: "Tool name and description clearly indicate 'Read-only' operation that 'Show version history' and 'Compares request/response schemas' to detect changes. Returns historical data in JSON format with no mutation or side effects." ## Use case AI agents call get_contract_versions to retrieve information from Trace without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere. ## Recommended policy (PolicyLayer) Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Trace: ```json { "version": "1", "default": "deny", "tools": { "get_contract_versions": {} } } ``` ## Other tools on Trace (190) - `delete_corpus` — Destructive — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/delete-corpus.md - `remove_dead_code` — Destructive — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/remove-dead-code.md - `repair_index` — Destructive — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/repair-index.md - `call_project_tool` — Execute — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/call-project-tool.md - `reindex` — Execute — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/reindex.md - `visualize_graph` — Execute — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/visualize-graph.md - `analyze_perf` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/analyze-perf.md - `assess_change_risk` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/assess-change-risk.md - `audit_config` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/audit-config.md - `benchmark_project` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/benchmark-project.md - `check_architecture` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/check-architecture.md - `check_claudemd_drift` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/check-claudemd-drift.md - `check_duplication` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/check-duplication.md - `check_edit_safe` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/check-edit-safe.md - `check_embedding_drift` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/check-embedding-drift.md - `check_quality_gates` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/check-quality-gates.md - `check_rename` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/check-rename.md - `compare_branches` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/compare-branches.md - `detect_antipatterns` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/detect-antipatterns.md - `detect_ast_clones` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/detect-ast-clones.md - `detect_communities` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/detect-communities.md - `detect_drift` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/detect-drift.md - `detect_topic_tunnels` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/detect-topic-tunnels.md - `diff_graph_snapshots` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/diff-graph-snapshots.md - `discover_claude_sessions` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/discover-claude-sessions.md - `discover_hermes_sessions` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/discover-hermes-sessions.md - `embed_repo` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/embed-repo.md - `explain_architecture` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/explain-architecture.md - `explain_symbol` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/explain-symbol.md - `export_decisions` — Read — https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp/export-decisions.md - …and 160 more: https://policylayer.com/tools/nikolai-vysotskyi-trace-mcp.md ## For agents This record is a snapshot. Live verdicts and the full registry: - Check every server in your MCP config at once: `npx -y policylayer stack` - Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md) - Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events` --- Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=nikolai-vysotskyi-trace-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/nikolai-vysotskyi-trace-mcp