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

Annotations already indicate a write operation (readOnlyHint=false) and non-destructive (destructiveHint=false). The description adds valuable behavioral context: FREE businesses cannot use this tool regardless of features, and a grace-period warning/verified resubscribe link must be shown before proceeding. This goes beyond annotations by specifying access restrictions and required UI interactions.

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 relatively short and begins with the purpose. However, it repeats the permission-checking requirement multiple times and could be more streamlined. Some sentences (e.g., 'FREE businesses cannot use this tool, regardless of individual feature rows') are slightly verbose for the core message.

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 (6 parameters, no output schema, no schema descriptions), the description is incomplete. It covers access controls but omits details about what the tool returns, how parameters interact (e.g., 'applyToAll' vs 'checkpoints'), and differentiation from similar tools like 'bulk_update_challenge_checkpoints'. The AI lacks enough context to use 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?

The input schema has 6 parameters with 0% description coverage (no schema descriptions). The tool description provides zero explanation of what parameters like 'startTime', 'applyToAll', or 'checkpoints' mean, leaving the AI unable to correctly populate them. This is a critical gap for a tool with many parameters.

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 'Update checkpoint dates for a challenge.' This identifies the resource (checkpoint dates) and action (update). However, it does not distinguish from sibling tools like 'bulk_update_challenge_checkpoints' or clarify whether it updates single or multiple checkpoints, leaving scope ambiguous.

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 preconditions: check business permissions, call check_business_tool_access, show grace-period warning, and never proceed when access is blocked. This guides when to invoke, but it lacks differentiation from alternative tools (e.g., when to use this vs bulk_update_challenge_checkpoints) and does not state when the tool is appropriate.

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