List media files

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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and closed-world, so the safety profile is covered. The description adds value beyond that by disclosing the result envelope (names/total/truncated), the default limit of 100, and the fact that results can be silently capped — a real behavioral trait the annotations do not express.

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?

Three tight sentences: what it does, what it returns with the cap caveat, then the intended use. The purpose is front-loaded and nothing is redundant filler.

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 two-parameter read-only listing tool, the description covers the operation, the glob semantics, the result shape including the truncation flag, and the primary use case. With no output schema present, spelling out the return envelope is exactly the missing piece an agent would otherwise have to guess.

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 both `limit` (with its default and minimum) and `pattern` (with glob examples and its "*" default) are already fully documented in the schema. The description repeats the default limit of 100 and the pattern-matching idea without adding syntax or edge-case meaning, so 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?

The description states a specific verb and resource ("Lists file names in Anki's media folder") and narrows it with the glob filter, which cleanly separates it from siblings like retrieve_media_file or store_media_file that move file contents. It never names an alternative explicitly, so it falls just short of full sibling differentiation.

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?

"Use it to check whether a file already exists" gives a concrete when-to-use scenario rather than leaving usage implied. It does not say when not to use it or point to a specific alternative such as retrieve_media_file for fetching contents, so no exclusions are provided.

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