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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so safety is covered. The description adds no behavioral context beyond the read semantics — nothing about what happens with an unknown or malformed media_ref, whether the reference resolves to a URL or metadata, or any scope limitation. Adequate but thin against the lower annotation-backed bar.

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?

A single front-loaded clause with a semicolon-joined routing hint; zero filler, and the disambiguation arrives after the action is established.

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-value explanation is not required, and the single-parameter surface is simple. The one remaining gap is provenance — nothing indicates that media_ref values come from account_media_list — which would have made it fully self-contained.

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 0%, so the description must carry the burden, and it only restates the parameter concept ('account media reference') which is tautological with media_ref. The only real semantics — the ^media_e1\.[A-Za-z0-9_-]+$ pattern and where such a reference is obtained — come from the raw JSON schema, not the description.

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 ('Read') plus a bounded resource ('one account media reference') and immediately contrasts it with the batch sibling. An agent can distinguish it from account_media_get_batch and account_media_list 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 names the alternative (account_media_get_batch) and the condition that selects it ('for multiple selections'), which is the core routing decision for this tool. It leaves account_media_list unmentioned, so the list-vs-get case is still left to inference.

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