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

Annotations already establish that this is a safe read (readOnlyHint=true) and not open-world, so the safety profile is covered. The description adds that no authentication is needed and enumerates operational limits (55s sync exec, 5 MB transfers), but it is mostly a content dump rather than behavioral disclosure about the tool's own operation.

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 key pricing table is front-loaded and information-dense, and every spec has some value. However the description is very long, and the SDK-install paragraph is essentially promotional material rather than something needed to select or invoke the tool, so it dilutes the signal.

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?

With no output schema, the description must convey what the tool returns, and it does so thoroughly: full tariff specs, per-second/hour/month pricing, billing model, execution and file-size limits, and supported runtimes. Nothing an agent needs to call or interpret this zero-parameter tool is missing.

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 tool takes zero parameters, so per the baseline this dimension starts at 4. The description correctly conveys that nothing is required ('Requires: nothing'), which is consistent with the empty input 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 identifies a specific resource (sandbox tariffs, pricing, and limits) with enough detail (instance sizes, runtimes) that it is unmistakable against siblings like list_plans or get_order_limits. It never states an explicit verb ('returns'/'lists') and does not name a sibling it differs from, so it falls short of the top tier.

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?

Usage is only implied: the pricing context suggests calling it before choosing a sandbox tier, and 'Requires: nothing' plus the SDK note hints at an alternative path for coders. It does not say when to prefer this over list_plans/get_order_limits or state any exclusion, leaving the agent to infer the timing.

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