get_ads_by_id

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

Annotations already declare readOnly, idempotent, non-destructive, openWorld, so the safety profile is covered. The description adds real behavior beyond that: a hard 1-100 batch bound, per-account ID uniqueness, the effect of return_target, and an account-resolution fallback chain (TELEGRAM_ADS_ACCOUNT_ID, then token owner). It is silent on what happens with unknown or cross-account IDs, which is a minor remaining gap.

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 short lines, front-loaded with the core action, then limits, then the optional flag, then the default resolution rule. No redundant restatement of the name or title, and every sentence adds a distinct fact.

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?

This is a simple read tool with an output schema, so return shape need not be explained, and annotations cover safety. The description covers batching, account resolution, and the optional targeting payload; error behavior for missing IDs is the only notable omission.

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 carries the full burden, and it does so for all three parameters: ad_ids (count limits and account-scoped uniqueness), account_id (env-var and token-owner fallback), and return_target (pulls in targeting settings). Only the array-of-integers typing is left to the schema, which is acceptable.

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 ads by their IDs) and states the key scoping fact that ad IDs are unique within an account. It implicitly contrasts with the listing sibling (list_ads) by emphasizing lookup by ID, but never names the alternative explicitly.

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 concrete usage context (batch of 1-100 IDs, IDs unique per account) and a defaulting rule for account_id, which tells the agent how to call it. It does not state when to prefer this over list_ads or get_ads_stats, so routing between siblings is left to inference.

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