Stream Text

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

No annotations exist, so the description carries the burden. It does disclose useful behavior beyond the signature: writing is live and 'with no blip', the clear-on-empty-string convention, and where each slot renders. Missing are state prerequisites, failure modes, and rate/refresh behavior for a live overlay.

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?

The meaning is front-loaded in the first clause, followed by the slot map and the clear convention. Dense but nearly every phrase carries information; the nested parentheses make it slightly harder to scan than it needs to be.

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 overlay tool with an output schema, the description covers the important semantics, but it omits the operating precondition (an active stream) and any error/conflict behavior with the other stream_* writers. That gap matters for correct invocation.

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 coverage is 0% (both params are bare strings with no enum), and the description compensates well by enumerating the four slot values with their screen positions and by defining text='' as a clear. It leaves open whether other slot values exist or whether text is length-limited.

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 concrete verb and resource: put a line of text on the live stream overlay. It also distinguishes itself from the one sibling that overlaps ('chat_overlay writes it on its own'), though the many stream_* siblings (stream_visual, stream_scene, stream_page) are not contrasted.

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?

Usage is implied by the slot enumeration and the live-context phrasing, and the chat_overlay aside hints at when not to use this. But there is no explicit statement of prerequisites (e.g. stream_start must be running) or when to prefer stream_visual/stream_scene instead.

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