Preflight

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

The description discloses key behavioral traits beyond annotations: the tool returns a readiness condition (`ready`), instructs halting when false, and reveals that all editing tools depend on the open window. The readOnlyHint annotation is consistent with the check/report behavior, and no contradiction exists.

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 two sentences with no filler. The core purpose is front-loaded, followed immediately by the critical usage directive and consequence. Every clause contributes actionable information.

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 zero-parameter preflight tool, the description is complete: it names the operation, gives the call order, provides the failure condition, and explains the underlying dependency. An output schema exists to describe the return values, so no additional return-format detail is needed.

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?

With zero parameters and 100% schema description coverage, the baseline is 4. The description does not need to explain parameters, and it fulfills the requirement by adding no irrelevant parameter detail.

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 states a specific verb ('Check') and resource ('Aseprite is connected') and adds the reporting function ('report what this session can do'). This clearly distinguishes preflight as a connectivity/session-check tool from sibling editing tools like layer, draw, and transform.

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?

Explicitly instructs 'Call this FIRST in any pixel-art task' and provides the stop condition ('stop if ready is false'). It also explains why this matters, that every editing tool writes into the user's open Aseprite window with no useful fallback, giving the agent a clear decision rule and rationale.

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