describe

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

With no annotations, the description carries the full behavioral burden. It discloses that the operation reads a loaded document and returns a formatted table, and that the expression should resolve to numbers, but it says nothing about permission/auth (not applicable), error behavior for empty or non-numeric matches, or whether the document alias must already be loaded.

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 summary sentence is front-loaded and precise, the Args block is tight, and the Returns line is short. Nothing is redundant for a tool of this size.

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?

An output schema exists, so the Returns line is technically redundant, but the description omits the edge cases an agent needs: what happens when the JSONPath matches zero numeric values, mixed types, or an unloaded alias. That leaves a meaningful gap for a statistics tool.

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%, so the description must compensate, and it does: alias is explained as the loaded document's alias and expression is explained as a JSONPath resolving to numbers with a concrete example ('$.orders[*].total'). The only gap is that 'expression' does not state the expected syntax flavor or failure mode.

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 and resource ('Get a full statistical summary of numeric values matched by a JSONPath') and enumerates the exact metrics returned, which distinguishes it from thin siblings like sum_values, count, and min_max. It stops short of naming those siblings explicitly, so the differentiation is inferential rather than stated.

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?

Usage is implied by the phrase 'numeric values matched by a JSONPath' and by the comparison to pandas .describe(), but there is no explicit guidance on when to prefer this over sum_values/count/min_max or what to do when the path matches non-numeric or zero values.

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