plan_update

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

The annotations include 'openWorldHint: true', indicating the tool may interact with external systems, and 'destructiveHint: false', indicating it is not destructive. The description adds that it 'builds' an update, which is non-destructive. Since annotations already cover safety, the description adds minimal behavioral context beyond clarifying the non-apply nature. No contradiction found.

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, consisting of one sentence with an example. It is front-loaded with the core purpose ('Build (not apply) an update') and the example clarifies the changes format. No unnecessary detail.

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 the tool's complexity (building an update with flexible changes) and the lack of schema descriptions, the description provides a key example but does not explain the full range of possible changes or how to specify the entity and market. The presence of an output schema may cover return values, but parameter semantics are incomplete. The description is sufficient for basic use but leaves gaps for comprehensive use.

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?

The input schema has no descriptions, and the schema description coverage is 0%. The description explains the format of the 'changes' array with examples, which is helpful, but it does not provide details on other parameters like 'entity', 'market', or 'note'. Since coverage is 0%, the description must compensate, and it only partially does so for 'changes', leaving other parameters ambiguous.

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 'Build (not apply) an update', using a specific verb 'Build' and resource 'update'. It distinguishes itself from the sibling 'apply_plan' by explicitly noting it does not apply. The description also provides concrete examples of the changes format, making the purpose clear and differentiating from related tools.

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 indicates that this tool builds an update rather than applying it, which serves as a clear usage guideline differentiating it from 'apply_plan'. However, it does not explicitly mention when to use this tool versus alternatives, such as 'plan_create' or 'apply_plan', or provide context on when to use each. The exclusion is implied but not exhaustive.

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