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

Far exceeds what the annotations carry. It discloses refusal conditions (already goes to that platform/account or posted in the last day, time passed or changed, Substack), the idempotency contract with clientRequestId and the replayed:true response, and the content fallback logic. These are exactly the behavioral traits an agent cannot derive from readOnlyHint/idempotentHint alone.

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-loads purpose and the sibling distinction before the operational detail, and each sentence carries real information (refusals, idempotency, content sourcing). It is dense and reads as one long block rather than clearly segmented sections, which taxes scanning, but there is little 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?

An output schema exists, so return values needn't be spelled out, and the description still notes it returns the new version(s) and scheduled time. Combined with the refusal conditions, account-selection path, and idempotency rules, an agent has everything needed to call this 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%, so the baseline is 3, but the description adds genuine semantics beyond the schema: the omission-fallback rule for content ('the same platform's version, else the longest that fits... shortened to fit with adjustedPlatforms and warnings'), and the account-selection requirement. It clarifies behavior rather than merely restating field descriptions.

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 ('Add a platform (or another account on a platform) to a Note that is already scheduled') plus the downstream effect ('so it posts there at the same time as the Note's other versions'). It explicitly distinguishes itself from the nearest sibling, schedule_note, so an agent can route correctly without opening either schema.

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?

Gives an explicit selection rule ('Use this, not schedule_note, whenever...') and explains what schedule_note would do instead (create a separate Note). It also enumerates the platforms in scope and the operating rule 'Ask the writer, never pick', leaving nothing to inference.

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