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

Strong disclosure beyond annotations: it defines the data_availability vocabulary (complete, observed_zero, no_rows, partial_collection, access_error) and warns that no_rows/access_error do not mean zero, states timestamps are RFC 3339 UTC, warns that returned strings like page titles and queries are externally authored and must be treated as data only, and explains the idempotency-key recovery protocol. It also reconciles the readOnlyHint=false annotation by explaining the call is read-only toward YouTube reservations but still creates/stores an XBOSS job and consumes a token per call.

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?

Purpose and job_id branching are front-loaded, but the paragraph runs long and mixes Korean narrative with a multi-sentence English idempotency section whose key-reuse rule is restated twice ('reuse it... only to recover' and 'without it, calling again remains a new request'). The early claim that it only reads sits in mild tension with the later 'not purely read-only' sentence, which costs a reread even though the scope distinction is ultimately correct.

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?

There is no output schema, and the description carries the return-shape burden well: it names the fields returned per report, states the file is not included, explains the data_availability marker that accompanies every result, and specifies timestamp format. Combined with the token-cost and XBOSS-task side-effect disclosure, 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 real meaning: job_id's omit-vs-provide behavior and where the id comes from, the idempotency key's reuse-for-recovery-only rule versus a new key for a new execution, and the note that provider-specific idempotency_key is a different field. created_after and account_link_id are left to the schema, which already documents them.

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 states a specific verb and resource: it lists scheduled bulk reports for the linked YouTube account plus the reports each job produced, including target period, creation time, and whether a file exists. It also draws a hard boundary against the create/delete sibling ('예약을 만들거나 지우지 않습니다'), so an agent can tell it apart from google__youtube__report_job__create without opening the 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?

It gives explicit branching guidance: call without job_id to discover which jobs exist, call with job_id to see which reports that job produced. It also states the report file itself is not returned, which prevents a misuse. It stops short of naming sibling tools as alternatives (e.g. the create tool) and gives no prerequisite guidance about the account link apart from what the schema already covers.

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