MongoDB Search: Engine, Relevance, and Operations

MongoDB Search guidance for Atlas and self-managed deployments. This skill contains 24 rules across 6 categories. It focuses on deployment routing, index/mapping guardrails, query composition, hybrid orchestration, and production operations.

Critical Warning

Search behavior is release-sensitive. Before applying any advanced pattern, confirm deployment track (Atlas vs local Atlas vs self-managed Community), MongoDB version, and feature status (GA/Preview/Public Preview).

When to Apply

Use this skill when you are:

• Creating or updating Search indexes and mappings

• Building $search and $searchMeta pipelines

• Choosing analyzers, autocomplete settings, synonyms, and facets

• Debugging relevance quality or response shape (highlight , returnStoredSource , returnScope )

• Triaging Search alerts, metrics, and index build failures

• Deploying Search on MongoDB Community (mongot , searchCoordinator )

• Orchestrating hybrid retrieval with $rankFusion and $scoreFusion

Scope Boundary with mongodb-ai

This skill owns search engine semantics and operations. Hand off to mongodb-ai when the request is primarily about:

• Embedding model/provider compatibility (including Voyage input_type )

• RAG ingestion/chunking and agent-memory design

• Vector retrieval tuning strategies centered on model behavior

Rule Categories by Priority

Priority Category Impact Prefix Rules

1 Deployment Modes and Release Gates CRITICAL deploy-

5

2 Index Architecture and Mappings CRITICAL index-

6

3 Query Composition and Relevance CRITICAL query-

5

4 Hybrid and Vector Interop HIGH hybrid-

3

5 Operations and Troubleshooting HIGH ops-

4

6 Skill Boundary Rules MEDIUM boundary-

1

Quick Reference

1. Deployment Modes and Release Gates (CRITICAL) - 5 rules

• deploy-track-detection

• Detect Atlas vs local Atlas vs Community before commands

• release-status-gating

• Tag guidance as GA/Preview/Public Preview

• community-preview-safety

• Check current release status before recommending Community Search for production

• community-prereqs-mongot-auth

• Replica set, keyfile auth, and searchCoordinator user requirements

• community-mongot-health-check

• Validate mongot health and queryability before tuning

2. Index Architecture and Mappings (CRITICAL) - 6 rules

• index-static-vs-dynamic-mappings

• Prefer static mappings, constrain dynamic scope

• index-fields-limit-guardrail

• Respond to Search Max Fields Indexed alerts

• index-ngram-limit-guardrail

• Control nGram/edgeGram/autocomplete field growth

• index-analyzer-selection

• Align analyzer and tokenizer with operator intent

• index-synonyms-lifecycle

• Safe synonym source design and update behavior

• index-facet-field-typing

• Correct facet-compatible field typing

3. Query Composition and Relevance (CRITICAL) - 5 rules

• query-compound-structure

• Use must /should /mustNot /filter correctly

• query-operator-selection

• Pick text vs phrase vs autocomplete vs queryString

• query-score-tuning

• Tune scoring intentionally with measurable guardrails

• query-return-shape

• Use highlight , returnStoredSource , and returnScope correctly

• query-facet-pipelines

• Prefer $searchMeta for facet-only metadata

4. Hybrid and Vector Interop (HIGH) - 3 rules

• hybrid-lexical-prefilter-routing

• Route simple vs advanced prefilters correctly

• hybrid-fusion-stage-gates

• Enforce version and stage limits for fusion operators

• hybrid-strategy-selection

• Choose fusion-only vs two-stage retrieval thoughtfully

5. Operations and Troubleshooting (HIGH) - 4 rules

• ops-alerts-and-metrics-runbook

• Alert-to-action runbook for top Search incidents

• ops-index-build-failure-triage

• Structured triage for Pending/Building/Stale/Failed

• ops-log-driven-debugging

• Debug with explain, metrics, and health signals

• ops-reindex-change-management

• Safe rollout and rollback for index definition updates

6. Skill Boundary Rules (MEDIUM) - 1 rule

• boundary-handoff-to-mongodb-ai
• Transfer provider/model concerns to mongodb-ai

Docs Quick Map

See references/docs-navigation.md for release-sensitive routing and boundary checks.

Production Readiness Checklist

• Confirm deployment track and MongoDB version before selecting syntax.

• Confirm release status for every feature (GA/Preview/Public Preview).

• Confirm index definitions are constrained and alert-safe.

• Confirm query design (compound , operator choice, scoring) with explain and metrics.

• Confirm hybrid stage/version compatibility before rollout.

• Confirm boundary handoff to mongodb-ai for provider/model semantics.