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

Beyond the readOnly/idempotent annotations, the description discloses a critical behavioral nuance: empty asset_types/channels/connected_accounts lists mean UNRESTRICTED, not missing, and warns never to stop on them. It also adds plan-tier constraints for film renders, which the annotations alone do not convey.

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?

Four tight sentences, each earning its place: the first front-loads the tool's purpose, the second gives the invocation order, the third prevents a dangerous misinterpretation, and the fourth states a concrete constraint. No 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 zero-parameter read-only tool with an output schema and strong annotations, the description covers everything needed to call it correctly: what it returns, when to call it, how to interpret the response, and how plan restrictions affect downstream rendering.

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 tool takes zero parameters and schema coverage is 100%, so there is no parameter documentation burden. The description adds value by listing what the response will tell the agent, but this is not parameter semantics; baseline 4 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 names a specific verb and resource ('Get the connected Siren workspace') and enumerates the returned fields: plan, key scopes, auto-post setting, and daily limit. This clearly distinguishes it from sibling tools like get_brand_dna or get_run that target different resources.

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?

It explicitly tells the agent when to invoke the tool: 'Call this first to learn what the account can do before generating.' It also gives a decision rule about empty lists being unrestricted, and ties film-render capability to plan tier, so the agent knows how to act on the result.

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