Add a server to the rack

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

With no safety annotations beyond the title, the description carries the full burden and does so excellently. It discloses that the operation is an idempotent upsert ('Overwrites an existing entry with the same name'), that it does not start the child process, does not validate the command, and is a local write only. This is far more than the structured annotations 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 three sentences with no filler. It front-loads the primary purpose, then adds side-effect warnings, then provides sibling routing. Every sentence earns its place.

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 tool is simple, the input schema covers all parameters, and an output schema exists. The description fully covers behavior, side effects, idempotency, validation limits, and sibling alternatives, leaving no significant gap 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 schema already documents all three parameters in detail. The description adds a small amount of meaning by explaining how 'name' connects to route_task and rack_remove and by clarifying that 'command' is not validated, but it does not substantially extend the parameter semantics beyond the schema.

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 action: 'Register an MCP server on the in-memory rack so later route_task calls can target it by name.' It names the specific resource (the rack) and the purpose, and it differentiates itself from siblings by explicitly mentioning route_task, list_rack, and rack_remove.

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 practical usage context: it says the tool is for registration, does not start or validate the child process, and explicitly points to list_rack for inspection and rack_remove for deletion. It could be slightly stronger by explicitly stating when not to use this tool, but the alternatives are clear.

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