get_aria_accessibility_tree

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

With no annotations, the description carries the burden of disclosure. It states the return format (YAML), the default selection of the failed action or last snapshot, and the token cost reduction. This is meaningful behavioral context, though it does not describe edge cases like missing traces or performance implications.

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 well-structured sentences with no filler. The first sentence front-loads the core action and resource, the second explains cost and parameter behavior. Every clause 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?

The tool is simple (2 params, 1 required) and the description covers the essential behavior: return type, default action selection, and cost rationale. The absence of an output schema is mitigated by specifying 'YAML' as the format, and no prerequisites or error conditions are necessary for this straightforward getter.

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?

Schema coverage is 100%, so baseline is 3. The description reinforces the action_index default behavior but does not add new meaning beyond the schema's own parameter descriptions. It adds no extra detail for trace_path, so it does not exceed the baseline.

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 specifies the action ('Returns') and the resource ('ARIA accessibility tree (YAML) for a frame snapshot in the trace'). It also differentiates from sibling tools by highlighting the 90% token cost reduction vs raw HTML, making its purpose distinct.

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 provides clear context for when to use the tool (e.g., to access an ARIA tree for a specific action or failure analysis) and explains the default behavior of action_index. While it does not explicitly mention alternative tools, the cost advantage and frame-snapshot scoping give implicit guidance without being misleading.

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