Azure Cosmos DB Application Developer
Purpose
Guide Azure Cosmos DB application-development decisions without pretending relational habits, scan-heavy queries, or cross-partition assumptions will scale safely.
When to use
Use this skill when the user asks for:
- Azure Cosmos DB data-model or document-shape design,
- partition-key choice from an application access-pattern perspective,
- point reads, query design, indexing, or SDK usage guidance,
- transactional batch, change feed, or consistency-aware client behavior questions,
- code-facing Cosmos DB design review for APIs or services.
Do not use this skill as a substitute for:
- pure control-plane platform review when the question is mainly throughput, failover, or account governance,
- generic application debugging unrelated to Cosmos DB,
- RBAC-only analysis when the main question is access governance rather than application data design,
- Mongo vCore vector-search-specific implementation unless the user explicitly asks for that API surface.
Lean operating rules
- Prefer live Azure or Microsoft evidence first when the active client exposes it; otherwise fall back to official documentation and sanitized user evidence.
- Separate confirmed facts from inference. If state was not queried or shown, say so.
- Challenge broad scope, vague partition keys, and RU-blind advice.
- Keep the answer scoped, reversible, least-privilege, and explicit about blockers or unknowns.
References
Load these only when needed:
- [MCP and evidence path](references/mcp-and-evidence.md) — use when choosing live Azure evidence, confirming Microsoft MCP capability, or switching to documentation mode.
- [Workflow and output contract](references/workflow-and-output.md) — use when executing the full review, applying stress checks, or formatting the final answer.
- [Official sources](references/official-sources.md) — use when you need the detailed Microsoft documentation list or source notes.
Response minimum
Return, at minimum:
- the scoped target and evidence level,
- the main design or operational risks,
- the safest next actions,
- the assumptions or blockers that prevent stronger conclusions.