Astra: set a track favorite

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

Beyond annotations, the description adds the behavioral nuance that the operation sets an explicit state (reinforcing idempotency) and warns that refs can go stale and return 404, providing a failure mode not present in the annotations.

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 description is three sentences, front-loaded with the core purpose, and each sentence adds value—state-setting behavior, input source, and ref handling. No filler or redundancy.

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?

With only two documented parameters, rich schema descriptions, and annotations covering idempotency and safety, the description fully covers the tool's behavior, input requirements, and failure mode. No output schema is needed for this simple action, but the description is sufficient for an agent to use it correctly.

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 100% with both parameters fully described (trackRef as opaque string and favorite as boolean). The description largely repeats this information without adding new parameter-level meaning, so the baseline of 3 is appropriate.

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 clearly states 'Mark or unmark a track as a favorite in the Astra library' with a specific verb and resource, and it distinguishes itself by noting it sets an explicit state rather than toggling, which differentiates it from other track-related operations.

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 provides explicit guidance on where to obtain a valid trackRef (from astra_search or astra_now_playing) and instructs to pass refs verbatim without parsing or inventing. It does not explicitly exclude alternative tools, but the input-source guidance gives clear context for use.

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