add_once_only_controller

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

With no annotations provided, the description carries the full burden and clearly reveals the key behavioral trait: children run only on the first iteration and are skipped later. It also notes the typical parent type. It does not cover side effects like plan modification or errors, but the primary runtime behavior is well disclosed.

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 definition is two sentences with no filler: the first states the action and scope, the second explains behavior and a concrete use case. The most important information is front-loaded and every clause 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?

For a simple 'add element' tool, the description covers purpose, placement, behavior, and a typical use case. Gaps remain around planId/name semantics and response behavior, but given the tool's low complexity, this is reasonably 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 0%, so the description must compensate, but it only vaguely refers to 'the given parent' for parentId. It does not explain planId or name at all, and the default name is only implied by the schema default. This is insufficient to fully clarify parameter meaning.

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 uses a specific verb and resource ('Add a Once Only Controller') and identifies the target parent location ('under the given parent'), immediately distinguishing it from sibling add_* tools. It further explains the core behavior of the added element, making its purpose unambiguous.

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?

Explicit usage context is given: 'use it for a login before a looping scenario' and mention of the find_breaking_point scenario. However, it does not name alternative tools or state when not to use it, so it falls short of full exclusion guidance.

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