Strong foundation with 23 well-named tools following verb_noun convention (list_, get_, vb365_). All tools have descriptions (avg ~150 chars, within 10-1024 baseline). Input schemas present with type definitions and parameter descriptions. However, output schemas are not documented in the source code, LLMs cannot predict response structure. Error handling is minimal; no recovery guidance or actionable error messages visible. Security is well-designed (confirm-gated writes, audit logging, no secrets in params), but this is implementation-level, not definition-level. Read-only tools dominate (17/23), which is appropriate for a backup system. Write tools (job_action, restore_item, generate_report) properly gate with two-call confirmation pattern.

• Document output schemas for all 23 tools. For each tool, specify the response structure: field names, types (string, integer, array, object), and nesting. Example: vb365_list_jobs returns {jobs: [{id: string, name: string, status: string, lastRun: ISO8601, nextRun: ISO8601}], total: integer}.
• Add min/max bounds to numeric parameters. E.g., limit: integer (1 - 1000, default 200), days: integer (1 - 365, default 30), rpo_hours: number (0.5 - 168, default 24). Include these in parameter descriptions.
• Convert string parameters to enums in schemas. vb365_org_inventory.kind should be enum: [users, groups, sites, teams]. restore_item.item_type should be enum: [mailbox, onedrive, site, teams]. restore_item.restore_mode should be enum: [inplace, export_pst, alternate].
• Add error handling guidance to write tools. job_action, restore_item, generate_report, org_sync, proxy_action should document: (1) what errors can occur (invalid ID, permission denied, API timeout), (2) whether they are retryable, (3) what the LLM should do next (e.g., 'If job_id is invalid, call vb365_list_jobs to find the correct ID').
• Ensure response fields match parameter names across tools. If vb365_list_jobs returns job_id, then job_action must accept job_id (not jobId). Verify field naming consistency in the implementation to prevent LLM confusion.