Render (read)

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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered; the description adds value by disclosing that progress is 'derived from percentage and error' and that codecs are only returned when `format` is supplied. It does not mention preconditions (e.g. a project needing to be open) or failure modes.

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 scope sentence followed by a dense action:params list with zero filler; every line either names an action, its inputs, or its return content.

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 five-action read tool with an output schema and full annotations, the description covers what each action returns, so return values are not overloaded. Missing only environmental preconditions and error behavior, which is a minor gap given the structured coverage.

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 effectively a generic `op` bag that explicitly defers to the description, so the description carries real weight by naming each action's parameters (format, codec, audio) and clarifying that 'natural names work everywhere'. What it lacks is any type/format detail for those arguments beyond the natural-name note.

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?

Opening sentence gives a specific verb and resource ('Read render state, no side effects') plus the intent ('find ids and check results'), and the five enumerated actions spell out exactly what can be read. An agent can distinguish this from render_write/render_delete purely from the text.

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?

The phrase 'use it to find ids and check results' gives a concrete use case, and the per-action list makes selection among its own actions unambiguous. It stops short of naming sibling alternatives (e.g. render_write for changes, describe_action for deeper param docs), so there is no explicit when-not guidance.

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