ck_route

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

The description states 'Read-only — no session state is changed,' covering key behavioral trait beyond annotation absence. It explains parameter effects like risk_tier filtering and allowed_agents restriction. However, it does not detail what happens if budget is exceeded or other edge cases, but it is still clear.

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 concise with only 4 sentences, front-loaded with purpose, then read-only flag, then parameter highlights, then alternatives. No redundant 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?

The description notes that the tool returns 'a ranked list of agent recommendations with rationale,' which is sufficient given no output schema. It covers all parameters and provides usage context. Slight gap: no mention of error conditions, but overall complete.

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 baseline is 3. The description adds semantic value by explaining the effect of risk_tier (filters agents by clearance) and allowed_agents (restricts to specific IDs), which goes beyond schema definitions.

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: 'Recommend the best available AI agent for a given task based on security tier, remaining budget, task type, and past performance data.' It also explicitly notes it is read-only and distinguishes from siblings like ck_delegate and ck_cost_optimizer.

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 explicit usage guidance: 'Use ck_route to pick an agent, then ck_delegate to transfer the task. Use ck_cost_optimizer for a price-focused comparison without routing.' This tells the agent when to use this tool and what alternatives exist.

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