decrypt

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

Discloses side effect: writes to output.md and returns path. With no annotations, this covers critical behavioral traits, though error conditions are omitted.

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 concise paragraphs: main action first, then args list. No wasted words, front-loaded with purpose.

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?

For a 2-param tool with an output schema, description covers purpose, side effect, and parameter usage completely. No missing critical aspects.

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?

Provides crucial detail beyond schema: ref can be a JSON object with 'ref' field, and key_id must come from encrypt tool. Schema coverage was 0%, so description fully compensates.

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?

Clearly states 'Decrypt an encrypted ref's text' with specific verb and resource. Distinguishes from sibling 'encrypt' tool by implying the inverse operation.

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?

Explicitly requires key_id from encrypt tool as prerequisite. No explicit when-not-to-use or alternatives, but context is clear for a simple decryption task.

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