List Recent Photos in Chat

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, and openWorldHint=true, so the safety and idempotency profile is fully covered. The description adds only the conceptual scope (photo messages in a chat) and the download hand-off, with no detail on filtering behavior, ordering, or pagination.

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?

Two sentences, no filler, with the core capability stated first and the cross-tool routing second. Every clause earns its place and nothing is repeated from the schema or annotations.

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 an output schema present, return values need no explanation, and the annotations cover the safety profile, so the description only needs to establish scope and routing — which it does. It could be slightly more complete by clarifying what 'inspect' entails or how results are ordered/limited, but no critical calling information is missing.

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 100% across all four parameters, so `limit`, `source`, `account`, and `chat_id` are fully documented in the schema. The description contributes no additional parameter meaning (e.g., how `source` interacts with the results or default ordering), so the baseline 3 applies.

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 ('List and inspect photo messages within a chat'), and carves out a boundary against a sibling action by naming `download_media` for the download case. An agent can tell this is a read-only listing of image messages rather than a media-info or message-listing tool.

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 usage context ('Use when auditing or finding images sent in a conversation') and routes downloading to `download_media`. It stops short of a full when-not statement, and the named alternative covers a different action rather than a competing list tool, so it is clear but not exhaustive.

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