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

The readOnlyHint annotation already marks this as a read operation, and the description adds substantive behavioral context beyond that: it does not return a position list, only aggregate KPIs, and it will return a refusal if the MCP-service is not connected. This is genuinely useful operational detail that the annotation alone does not provide.

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 compact and front-loaded: the core behavior and return fields come first, followed by the key limitation and sibling pointer, then the access condition. Every sentence carries necessary information without repetition or filler.

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?

Even without an output schema, the description names all four return KPIs. It covers the tool's scope, its limitation, the alternative tool for detailed positions, and the access/failure scenario. For a read-only aggregate tool with six optional, well-documented parameters, this is complete enough for an agent to call it correctly.

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 input schema already documents every parameter, including period options and region code formats. The description adds no parameter-level detail beyond saying results are produced 'under a given filter', so the baseline score of 3 is appropriate.

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 names a specific resource and result: an aggregated KPI summary over 44-FZ contract execution line items. It lists the exact return metrics (totalSum, totalQty, contracts, suppliers) and explicitly distinguishes itself from search_contract_executions by stating it does not return position details. This is a concrete verb-plus-resource statement with clear sibling differentiation.

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 tells the agent exactly when to choose this tool versus the alternative: it returns only KPIs, and for actual positions it directs to search_contract_executions. It also states the access prerequisite (the MCP-service must be enabled by a KRAFOOT manager) and the failure outcome, leaving no ambiguity about when the tool is appropriate.

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