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 fully covered. The description adds that alert firing rules and per-source sizes are included, which is mild value, but says nothing about auth needs, whether addresses are stable across calls, or any regeneration behavior.

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?

One sentence, front-loaded with the core action ('Get the three overlay addresses'), then the enumerated outputs and the bonus contents. No filler and nothing that could be trimmed without losing information.

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 the description need not explain return values, and it still names the three overlay artifacts plus the ancillary size/timing data. Adequate for a zero-required-parameter read tool; only the absence of any sibling-routing or auth note keeps it from being fully complete.

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 language, wallRows and alertSeconds are already fully documented in the schema. The description adds no parameter meaning beyond that, which lands at the baseline 3.

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 and resource ('Get the three overlay addresses') and enumerates exactly what the three are: goal bar, supporter wall, alert. An agent immediately knows the payload, though it does not explicitly distinguish itself from adjacent siblings such as get_embed_code or get_share_assets.

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 'to add to OBS or any streaming software as a browser source' supplies the use context, which is more than nothing. But it gives no conditions, prerequisites, or guidance on when to pick this over the embed-code or share-asset siblings.

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