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

Annotations already declare destructiveHint=true and readOnlyHint=false, but the description goes well beyond them: the entry disappears from list_images immediately while quota is only freed after ~30 min cleanup, uploads can still be refused in that window, and Instagram copies survive deletion. This is exactly the hidden-behavior context an agent needs before calling an irreversible 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?

Front-loaded with the action and its purpose, then failure conditions, then side effects, then the caution. Every sentence carries operational information; there is no filler despite the length.

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?

An output schema exists, so return values need no explanation, and the description covers what an agent cannot infer: refusal conditions, delayed quota reclamation, Instagram copy retention, and the requirement to confirm with the user first.

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% and the single parameter already documents its accepted sources ('id' from list_images or the _img/... reference). The description reinforces where the id comes from but adds no syntax or format detail beyond the schema, so the baseline 3 applies.

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?

States a specific verb and resource ('Delete an uploaded image') with the scope qualifier 'for good' and the rationale (quota room). An agent can immediately distinguish it from delete_video, delete_page and other siblings without opening any schema.

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 states the precondition for success ('refused while a page uses it, as a draft or online'), how to diagnose it (list_images shows `used_by`), the remediation (remove from those pages and save or publish first), the unaffected case (Instagram posts keep their own copy), and the human-in-the-loop requirement ('Ask the user first').

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