Nexus MCP provides a single well-defined search tool with comprehensive parameter documentation and clear descriptions. The tool follows a verb_noun naming pattern (search) and includes detailed descriptions that explain WHAT the tool does, WHEN to use each model variant, and what factors affect performance. Input schema is complete with proper typing, constraints, and descriptions for all parameters. However, the server lacks output schema documentation, tool annotations for read-only/idempotent semantics, and resource/prompt support. The descriptions are solid at ~180 chars for the main tool and ~100 chars per parameter, above the baseline average of 72 chars. No security issues detected as API keys are injected server-side via environment variables (OpenRouter API key management pattern is correct).

• Document output schema explicitly. Example: {"results": [{"title": string, "url": string, "snippet": string, ...}], "metadata": {"model_used": string, "processing_time_ms": number}}. This enables LLMs to extract and chain results.
• Add tool annotations to the tool definition: mark search as readOnlyHint=true and idempotentHint=true. This signals to MCP clients that the tool is safe for caching and optimization.
• Consider adding a 'research_report' resource type or prompt to guide multi-turn reasoning flows. E.g. 'Deep Research Summary' prompt that chains multiple search calls with sonar-deep-research.
• Replace server-side sampling logic with direct OpenRouter provider integration. Remove Sampling message handling and delegate model selection to the LLM's native capabilities.
• Validate and document timeout behavior: maxTokens range (1-4000) is documented, but document what happens when API times out and how retryability is handled.
• Add pagination guidance if applicable. Current tool returns a single result set; document whether large result sets are paginated or capped and how to retrieve more results.

Inferred effective spec: <=2025-11-25.

• Relies on Sampling (deprecated) - integrate directly with the LLM provider API