Context Engine MCP Server

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. It does an excellent job describing key behavioral traits: it's a session-initiating tool (not read-only), mentions caching, parallel execution, session management features, and telemetry collection. It also documents environment variables that control behavior. The main gap is not explicitly stating whether this is a long-running/async operation, though the session ID return hints at this.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is well-structured with clear sections (features, environment variables, returns) and uses bullet points effectively. It's appropriately sized for a complex tool. Minor deduction because the environment variables section, while useful, could be considered slightly verbose for a tool description versus configuration documentation.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a complex tool with 7 parameters and no annotations or output schema, the description provides substantial context about behavior, features, and session management. It explains what the tool returns (session ID) and how to monitor progress. The main gap is not explicitly describing the asynchronous nature of the operation or potential error conditions, which would be helpful given the complexity.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents all 7 parameters thoroughly. The description adds no specific parameter information beyond what's in the schema. The baseline of 3 is appropriate when the schema does all the parameter documentation work, though the description could have explained how parameters relate to the reactive features mentioned.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose with specific verbs ('start', 'initiates') and resource ('reactive PR code review session'). It distinguishes from siblings by focusing on session initiation rather than status checking (get_review_status) or other review methods (review_auto, review_changes, etc.). The opening sentence directly answers 'what does this tool do?'

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides clear context for when to use this tool: to start a reactive code review session with advanced features. It explicitly mentions using get_review_status to monitor progress, which helps differentiate from status-checking tools. However, it doesn't explicitly state when NOT to use it or compare with alternatives like review_auto or review_changes.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.