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

Annotations already declare readOnly and closed-world behavior, so the burden is lighter, yet the description still adds meaningful traits: it returns the pictures themselves, downsizes them to at most 1568 px, and caps at 10 per call. These output-shape details (format, resizing, limits) go beyond the structured fields.

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 tight sentences with no filler, and the primary action plus input source is front-loaded before the return-format detail. Every clause carries information an agent needs.

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 single-parameter read tool with no output schema, the description covers the action, input source, a motivating example, and the return format (decoded images, size cap, count limit). Nothing essential for correct invocation is missing.

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 coverage is 0%, so the description must carry the meaning of the single `urls` parameter, which it does by explaining the accepted URL sources. The 'up to 10 per call' phrasing also reinforces the maxItems constraint from the schema, compensating well for the missing schema descriptions.

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 ('Look at') plus resource ('photos stored in this workspace') and names concrete sources for the URLs (list_record_files, a record, an email attachment). It even gives a canonical use case ('compare a job's before and after photos'), letting an agent distinguish it from general file-reading siblings.

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?

It provides clear usage context by naming where the URL inputs come from and an example task (before/after comparison), which implies when to reach for this tool. It stops short of explicitly contrasting with alternatives like read_file or stating when not to use it, so no exclusion guidance.

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