pattern_select

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

With no annotations, the description must carry behavioral weight; it conveys the core navigation action and correctly flags the 1-based indexing convention. It does not disclose side effects on the current pattern/playback or error behavior for out-of-range indices, which is a clear gap.

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?

One sentence with no filler, front-loading the action and the key indexing detail. Every word 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?

For a one-parameter command with no output schema, the description gives the action, target resource, and indexing base. It omits invalid-index behavior, but that is a secondary detail for a simple navigation command, not a blocker.

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 schema provides only an integer 'index' with no description, so the note about 1-based FL indexing is genuinely additive and prevents the most likely off-by-one mistake. It does not document bounds, but for a single required parameter this is substantial compensation for 0% schema coverage.

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 names a concrete action ('Jump to pattern') and a specific selection mechanism ('by index'), which separates it from index-less siblings like pattern_find_by_name and pattern_jump_to_next/previous. It is not fully explicit about what 'jump' changes (active pattern vs transport position), so it stops 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?

The phrase 'by index (1-based in FL)' implies the tool is appropriate when the caller already has a numeric pattern index, which is a usable usage condition. However, it neither states when not to use it nor points to alternatives such as pattern_find_by_name or pattern_jump_to_next/previous.

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