ck_route

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the description's 'Read-only — no session state is changed' aligns with them but adds verbal clarity. The description additionally reveals that the tool returns a ranked list with rationale, which goes beyond basic annotations. A 4 is appropriate since the annotation set is already strong.

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?

Four concise sentences that are front-loaded with purpose, then parameter guidance, then sibling differentiation. Every sentence adds value without redundancy. No wasted words.

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?

Given that an output schema exists (noted in context), the description adequately covers return behavior ('Returns a ranked list of agent recommendations with rationale'). All four parameters are described both in schema and in text. Annotations cover safety. No gaps.

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%, baseline 3. The description adds clarifying context: 'task is a plain-language description', 'risk_tier filters out agents... defaults to medium', and 'allowed_agents restricts routing... omit to allow all'. This improves understanding beyond schema types and descriptions.

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 specifies the verb 'recommend' and the resource 'best available AI agent', and mentions criteria (security tier, budget, task type, past performance). It distinguishes from siblings like ck_delegate and ck_cost_optimizer by naming them and their purposes.

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?

Explicitly states when to use this tool ('Use ck_route to pick an agent'), provides a follow-up action ('then ck_delegate to transfer the task'), and names an alternative ('Use ck_cost_optimizer for a price-focused comparison without routing'). This leaves no ambiguity about usage context.

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