join_sheets

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

With no annotations, the description carries the full burden of behavioral disclosure. It details the live join behavior, truncation contract, refusal with candidate list when confidence is low, key normalization, null key handling, join types, and column suffixing. This is exceptionally transparent for a data tool.

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 a single dense paragraph that front-loads the core purpose, then logically covers optional behavior, key handling, and an explicit usage recommendation. Every sentence adds valuable information without redundancy or fluff.

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 description is highly complete given the tool's complexity, covering core behavior, edge cases, and output details. However, it does not explain the 'folder_path' parameter, which is part of the schema. While not critical to the main join functionality, this leaves a minor gap in the overall contextual picture.

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 has zero description coverage, so the description must compensate. It explains the semantics of left_on/right_on, join_type, limit, and the data.keys output field. It even covers edge cases like colliding column names and normalized matching, adding rich meaning beyond the raw parameter names.

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 states the tool 'Joins two sheets LIVE on key columns and returns the merged rows,' naming a specific verb and resource. It also distinguishes itself from sibling tools by explicitly recommending this tool over stitching filter_sheet results together.

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 includes explicit guidance on when to use this tool versus alternatives: 'Use this instead of stitching filter_sheet results together yourself.' It also explains the optional behavior of omitting key parameters and the server's decision-making process, giving the agent clear context for invocation.

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