api.describe

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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful context beyond the annotations: scope, completion state, undo behavior ('Undo: none'), and the possible error codes (internalError, invalidParams). However, it does not describe what the returned capability payload looks like, which matters for an introspection tool with no output schema.

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 core capability is front-loaded in the first sentence, followed by compact metadata lines. Some content ('Effect: read') duplicates the readOnlyHint annotation and the method-name restatement is mild filler, but overall it is efficient and scannable.

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 introspection tool with no output schema, the description should explain what the returned discovery payload contains (method list, schema shapes, limits). It hints at these categories but does not describe their structure, leaving the agent without a contract for the response. The error enumeration partially compensates.

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 and the schema is an empty object, so there is no parameter semantics to add. The baseline of 4 applies since the description has no parameters to misdescribe or omit.

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+resource ('Discover methods, schemas, limits and runtime capabilities') and identifies the underlying Anki-Connect method `api.describe` with its scope. It is clear what the tool does, though it never names the sibling api_execute to differentiate the discovery step from the execution step.

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?

There is no explicit when-to-use guidance, no exclusion criteria, and no mention of the closely related api_execute sibling. The agent must infer that this is an introspection call to be used before invoking other methods; nothing in the text confirms that or says when not to call it.

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