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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions the write_mode requirement, which is useful, but doesn't describe what 'delete' entails (permanent vs reversible, cascading effects, confirmation process), nor does it address rate limits, error conditions, or response format. For a destructive operation, this leaves significant gaps.

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 at just two short sentences, with no wasted words. The first sentence states the core purpose, and the second adds the critical permission requirement. Every element 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?

Given this is a destructive operation with no annotations, 0% schema description coverage, but with an output schema present, the description is minimally adequate. It covers the basic action and permission requirement but lacks details about the deletion behavior, parameter meaning, and relationship to sibling tools. The output schema reduces the need to describe return values, but more context would be helpful.

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 input schema has 0% description coverage, providing only a parameter name without context. The description doesn't mention the 'variable_id' parameter at all, offering no additional semantic information about what constitutes a valid variable ID, where to find it, or format requirements. However, with only one parameter, the baseline is 4, but the complete lack of parameter guidance in the description reduces this to 3.

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 action ('Delete') and resource ('an instance variable'), making the purpose immediately understandable. However, it doesn't differentiate this from sibling tools like 'delete_credential', 'delete_tag', or 'delete_workflow' beyond specifying the resource type.

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 one usage guideline ('Requires write_mode'), which provides important context about permissions needed. However, it doesn't specify when to use this versus alternatives like 'update_variable' or 'list_variables', nor does it mention any prerequisites beyond the mode requirement.

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