# sf_create_external_id_field Creates a custom field with externalId=true on a Salesforce object. External ID fields can be used for upsert operations and integration matching. The field is also automatically marked as unique. objectName: object API name fullName: field API name ending in __c label: display label type: field type (Text, Number, Email, or AutoNumber) length: max length for Text fields Agent View of the PolicyLayer registry record for `sf_create_external_id_field`. HTML page: https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-create-external-id-field ## Facts - Tool: `sf_create_external_id_field` - Server: Salesforce Metadata Mcp (`salesforce-metadata-mcp`) — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp.md - Install: `npx -y salesforce-metadata-mcp` - Homepage: https://github.com/semwalajay83-sem/salesforce-metadata-mcp - Risk category: Write (Medium risk) - Registry record: grade F, identity unverified - Server rate-limited: no - Parameters: 0 - Recommended policy verdict: Rate-limited ## Example call (MCP tools/call, JSON-RPC 2.0) ```json { "jsonrpc": "2.0", "id": 1, "method": "tools/call", "params": { "name": "sf_create_external_id_field", "arguments": {} } } ``` ## Why sf_create_external_id_field is rated Medium This tool creates a new custom field on a Salesforce object, which is a reversible data modification (Write category). The severity is high because creating external ID fields can materially impact integration behavior, data matching logic, and object structure in production Salesforce environments, potentially affecting multiple downstream systems that rely on external IDs for upsert operations. From the tool's own definition: "Creates a custom field with externalId=true on a Salesforce object... The field is also automatically marked as unique." ## Use case AI agents use sf_create_external_id_field to create or update resources in Salesforce Metadata Mcp, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Salesforce Metadata Mcp environment. ## Recommended policy (PolicyLayer) Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Salesforce Metadata Mcp: ```json { "version": "1", "default": "deny", "tools": { "sf_create_external_id_field": { "limits": [ { "counter": "sf_create_external_id_field_rate", "window": "minute", "max": 30, "scope": "grant" } ] } } } ``` ## Other tools on Salesforce Metadata Mcp (212) - `sf_bulk_delete_records` — Destructive — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-bulk-delete-records.md - `sf_delete_record` — Destructive — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-delete-record.md - `sf_delete_scratch_org` — Destructive — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-delete-scratch-org.md - `sf_activate_omniscript` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-activate-omniscript.md - `sf_create_apex_class` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-create-apex-class.md - `sf_create_apex_test_class` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-create-apex-test-class.md - `sf_create_apex_trigger` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-create-apex-trigger.md - `sf_create_flow` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-create-flow.md - `sf_create_scheduled_job` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-create-scheduled-job.md - `sf_create_scratch_org` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-create-scratch-org.md - `sf_deactivate_flow` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-deactivate-flow.md - `sf_deploy_metadata` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-deploy-metadata.md - `sf_devops_promote_work_item` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-devops-promote-work-item.md - `sf_execute_anonymous_apex` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-execute-anonymous-apex.md - `sf_install_package` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-install-package.md - `sf_promote_devops_work_item` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-promote-devops-work-item.md - `sf_run_apex_tests` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-run-apex-tests.md - `sf_send_email` — Execute — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-send-email.md - `sf_check_code_coverage` — Read — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-check-code-coverage.md - `sf_check_deploy_status` — Read — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-check-deploy-status.md - `sf_check_devops_commit_status` — Read — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-check-devops-commit-status.md - `sf_detect_devops_merge_conflict` — Read — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-detect-devops-merge-conflict.md - `sf_explore_slds_blueprints` — Read — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-explore-slds-blueprints.md - `sf_export_omnistudio_component` — Read — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-export-omnistudio-component.md - `sf_export_records` — Read — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-export-records.md - `sf_get_apex_test_results` — Read — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-get-apex-test-results.md - `sf_get_dataraptor` — Read — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-get-dataraptor.md - `sf_get_deployment_history` — Read — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-get-deployment-history.md - `sf_get_event_logs` — Read — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-get-event-logs.md - `sf_get_field_history` — Read — https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-mcp/sf-get-field-history.md - …and 182 more: https://policylayer.com/tools/io-github-semwalajay83-sem-salesforce-metadata-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=io-github-semwalajay83-sem-salesforce-metadata-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/io-github-semwalajay83-sem-salesforce-metadata-mcp