Media (read)

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

Annotations already carry readOnly/idempotent/non-destructive, and the description is consistent with them while adding real value: per-action return shapes ("raw JSON string plus parsed value"), pagination on browse_storage, and property selection on get_clip/list_clips. It does not disclose default limits, ordering, or what identifiers look like, which keeps it below a 5.

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 one-line purpose followed by a tight action-indexed list with no filler. The schema-level guidance is delegated to describe_action, which is efficient; the only blemish is the "+1 more" shorthand that hides a parameter rather than naming it.

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 polymorphic dispatcher over ten read-only actions, the description covers action selection, per-action scope, and required-vs-optional params, and it points to describe_action for full detail; an output schema exists so return values need no prose. Nothing an agent needs to call it correctly 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?

The schema is a generic op wrapper whose coverage is nominally 100% but adds no real detail, so the description must carry the parameter burden — and it largely does, listing params per action with '*' marking required ones. The "+1 more" truncation on list_clips and the absence of value formats (path syntax, keys, clip identifier form) leave a genuine hole.

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+resource ("Read media state, no side effects") and then enumerates all ten actions with their exact scope, so an agent knows precisely what is reachable here. The read/write/delete sibling triad makes the boundary obvious 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?

"use it to find ids and check results" gives concrete selection guidance, which is the classic pre-step for the mutating siblings (media_write, media_delete). It stops short of naming those alternatives or stating when-not to use it, so it is clear but not fully explicit.

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