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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds a useful behavioral gotcha beyond annotations: the embedded links preview is capped at 4 items, preventing a false assumption about collection size. This is meaningful extra context, though not exhaustive about pagination or ordering.

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 with no wasted words. The core purpose is stated first, and the important warning and alternative are packed into the second sentence. Every part earns its place.

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?

Given the tool's low complexity, no parameters, and no output schema, the description is complete: it states what rows contain, warns about the preview cap, and points to the sibling tool for full contents. An agent has enough information to invoke it correctly and interpret its results.

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 has zero parameters, so there are no parameter semantics to clarify. Per the baseline rule for 0-parameter tools, the description need not compensate for schema gaps; the 100% schema coverage and empty parameters make this dimension non-issue.

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 uses a specific verb ('List') and resource ('collections'), and adds what each row contains (section_title, link_count). It also distinguishes itself from split_get_collection_links by explicitly pointing there for real link contents.

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?

The description gives explicit routing guidance: use this tool for the collection overview, and use split_get_collection_links when real link contents are needed. The warning about the 4-item preview cap also clarifies when this tool's output could be misleading.

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