get_ad_stats

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

Beyond the annotations (which already declare readOnly/idempotent/non-destructive), the description discloses several non-obvious behaviors: the 300/86400 interval granularity, server-side rounding of bounds to interval starts, a hard cap of 1000 intervals, and ad-ID scoping to the selected account. It also explains account resolution (TELEGRAM_ADS_ACCOUNT_ID, else token owner), which is the kind of implicit-state behavior an agent cannot infer from the schema.

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 core action and time semantics are front-loaded in the first two lines, with constraints following. All five sentences carry information, though the line-broken formatting reads as an unordered list of facts rather than a deliberately structured brief.

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-shape explanation is correctly omitted, and the description covers the constraints an agent needs before calling (interval cap, rounding, account default). It stops short of saying what happens when the 1000-interval cap is exceeded or when ad_id is invalid for the account, which matters for a read call that can fail on bounds.

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 0%, so the description must carry the parameter burden and it largely does: from_time/to_time are Unix seconds in a half-open range, interval values mirror the enum, account_id has a documented default resolution chain, and ad_id is described as account-scoped. Minor omissions (the 86400 default, non-negative minimums) are already encoded in the schema itself.

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 opens with a specific verb and resource ("Get one ad's statistics") and bounds the scope with a half-open time range in Unix seconds. The word "one" implicitly separates it from the plural sibling get_ads_stats and from get_account_stats, but it never names those alternatives, so the differentiation is inferential rather than explicit.

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?

There is no when-to-use or when-not-to-use guidance, and none of the plausible alternatives (get_ads_stats for multiple ads, get_account_stats, get_account_report) are mentioned. The only routing-adjacent information is the account_id fallback rule, which is about defaults rather than tool selection.

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