refactor: dry - extract required resource ID helpers for Docs and Sheets

[aliwatters]

Summary

The Docs package repeats a 5-line document_id extraction+validation+URL-parsing block ~16 times across 3 testable files. Similarly, the Sheets package repeats a spreadsheet_id block 7 times. Extracting per-package helpers would eliminate significant boilerplate.

Location

Docs package (~16 instances):

• internal/docs/docs_formatting_testable.go: L128-138, L182-192, L227-237, L280-315, L355-365
• internal/docs/docs_content_testable.go: L48-51, L74-79, L105-110, L141-151, L203-222, L252-268, L308-311, L350-360
• internal/docs/docs_structure_testable.go: L19-45, L79-102, L158-172, L201-220, L262-267

Sheets package (7 instances):

• internal/sheets/sheets_tools_testable.go: L23-27, L69-73, L112-116, L166-170, L252-256, L304-308, L371-375

Category

Type: DRY Violation

Severity: Medium

Evidence

Docs — repeated 16x:

docID, _ := request.Params.Arguments["document_id"].(string)
if docID == "" {
    return mcp.NewToolResultError("document_id parameter is required"), nil
}
docID = common.ExtractGoogleResourceID(docID)

Sheets — repeated 7x:

spreadsheetID, _ := request.Params.Arguments["spreadsheet_id"].(string)
if spreadsheetID == "" {
    return mcp.NewToolResultError("spreadsheet_id parameter is required"), nil
}
spreadsheetID = common.ExtractSpreadsheetID(spreadsheetID)

Suggested Refactoring

1. Add extractRequiredDocID(request) (string, *mcp.CallToolResult) in docs package
2. Add extractRequiredSpreadsheetID(request) (string, *mcp.CallToolResult) in sheets package
3. Replace all inline instances with calls to the helpers
4. Consider a generic common.ExtractRequiredArg(request, key, extractFn) (string, *mcp.CallToolResult) if the pattern extends further

Effort Estimate

• Size: Small (< 1 hour)
• Risk: Low (simple extraction)
• Tests Required: Yes (existing tests must pass)

Acceptance Criteria

• extractRequiredDocID helper added and used across all 3 docs testable files
• extractRequiredSpreadsheetID helper added and used in sheets testable file
• ~23 instances of boilerplate replaced
• All existing tests pass

[aliwatters]

Claimed by AI Agent

Workspace: gsuite-mcp
Claimed at: 2026-02-10T08:54:07-06:00

This issue is now being worked on by an AI agent in workspace gsuite-mcp.

[aliwatters]

🔗 Batch Work: Working on this issue together with #15, #14 in a single PR.

Branch: refactor/issue-15-dry-helpers-batch