Generate Alt Text

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

With no annotations, the description adds valuable behavioral context: synchronous execution with possible latency and a credit cost. It does not mention overwrite behavior or the exact result format, but the disclosed traits go beyond the basic 'generate alt text' summary.

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 two sentences, front-loaded with the main purpose, and every word adds value. It efficiently conveys the operation, latency, and cost without redundancy.

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 the complexity (10 parameters, nested objects) and absence of annotations/output schema, the description covers the key operational aspects: what it does, how it behaves, and associated cost. It could have mentioned overwrite defaults or the exact return format, but the core context is sufficiently complete for an agent to decide whether to invoke it.

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 100%, so the baseline is 3. The description itself adds no parameter-specific meaning beyond what the schema already provides, but the schema is thorough enough that no compensation is needed.

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 verb ('Generate'), resource ('alt text'), and scope ('for an image URL'), which distinguishes it from the sibling tool generate_alt_text_from_file. The purpose is concrete and immediately understandable.

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 implies the tool is for generating alt text from a URL and notes that it runs synchronously and costs credits. It does not explicitly mention when not to use it or compare it to generate_alt_text_from_file, but the URL scope provides clear usage context.

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