Check credential status

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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description aligns (it is a diagnostic check). The description adds context about the credential's storage and validity, but doesn't mention output format or any potential side effects (e.g., network calls). Still, with strong annotations, this is adequate. No contradiction.

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?

Two sentences, front-loaded with the core function ('Diagnose the Canvas connection') and followed by clear usage instructions. Zero waste, every word adds value.

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?

Despite no output schema and no parameters, the description sufficiently covers what the tool does and when to use it. It doesn't describe the return format (e.g., JSON), but for a diagnostic tool, the guidance on usage is more critical. With strong annotations, this is complete enough.

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?

There are no parameters, so schema coverage is 100%. The description adds value by explaining what the tool examines (credential, storage, validity) without needing to explain parameters. Baseline for 0 params is 4, and the description enriches understanding of what 'status' means.

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's purpose: 'Diagnose the Canvas connection' and specifies exactly what it checks (which credential, where stored, whether it works). It distinguishes itself from sibling tools by focusing on connection/auth status, which no other sibling suggests.

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 when to use: 'Run this first when something fails, or before a scheduled job, to distinguish an expired session from a real error.' This provides clear guidance on timing and purpose, and implicitly differentiates from operations on Canvas content (courses, modules, etc.).

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