Call a qualified Hara Var

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

Annotations already indicate it's read-only and non-destructive. The description adds that it runs in a fresh restricted sandbox and that arguments are never concatenated into source, which provides security context. However, it doesn't detail error behaviors, output format, or side effects beyond annotations. It doesn't contradict annotations.

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 description is extremely concise, two sentences, front-loaded with the verb 'Invoke' and key context. Every word adds value, no filler.

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 5 parameters including nested `limits` and a complex recursion, the description lacks sufficient detail. It doesn't explain why `source` is a parameter (seems redundant with 'already-loaded' but maybe it's the source form), or how `limits` affect execution. Output schema exists, but that doesn't cover parameter guidance. The description leaves too much to infer.

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 description coverage is 0%, and the description doesn't explain any parameters individually. It mentions 'transfer-safe arguments' and 'qualified Hara Var' but doesn't specify what `namespace`, `symbol`, `source`, or `limits` mean. With 5 parameters and many nested, the description should compensate but doesn't.

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 the tool invokes a loaded Hara Var with transfer-safe arguments in a restricted sandbox, which is clear and specific enough. It distinguishes from siblings like hara_eval (which likely evaluates expressions) by focusing on calling a pre-loaded qualified variable, though it doesn't explicitly name these differences.

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 implies this tool is for invoking already-loaded vars, not loading them (distinguishing from hara_runtime_get and hara_eval), and mentions transfer-safe arguments for safety. However, it doesn't provide explicit criteria or when-not-to-use compared to alternatives, though context signals could help.

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