dify_instances

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

No annotations are supplied, so the description carries the full burden; it makes clear this is a read-only enumeration and, more valuably, discloses the default-instance fallback that governs how sibling tools resolve a missing alias. It does not mention ordering, empty-state behavior, or whether credentials are validated, which are minor gaps for a zero-parameter lister.

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 short sentences, zero filler, with the core purpose front-loaded and the default-instance rule placed second as supporting context. Nothing could be removed without losing 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?

With no output schema, the description compensates by listing the returned fields, and it explains the default-instance semantics that make the result actionable. Only minor details such as ordering or behavior when no instances are configured are absent.

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 no parameters, so the baseline is 4. The description still adds value by naming the fields returned and explaining the implicit default-instance selection that other tools rely on.

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 opens with a specific verb and resource (列出已配置的 Dify 实例) and enumerates the fields each entry carries (alias, site, debug port, default flag), so an agent knows exactly what it gets back. It does not explicitly contrast itself with siblings like dify_setup or dify_apps, which keeps it just short of a 5.

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?

It gives a clear reason to call it — discovering configured instances and their aliases — and adds the cross-tool rule that omitting an alias elsewhere falls back to the default instance. There is no explicit when-not-to-use or named alternative, but for a discovery tool the context is sufficient.

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