editMessageMedia

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

With no annotations, the description carries the disclosure burden. It adds meaningful behavioral detail beyond the schema: album editing restrictions and the distinct return type for inline messages (True instead of Message). It does not cover permissions, ownership requirements, or irreversible replacement of old media, so it is not a 5.

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 description is compact and front-loaded: purpose first, then the key constraint, then the return behavior. Every sentence contributes unique information with no filler or repetition.

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?

Given a nested media object, no annotations, and no output schema, the description covers the most important behavior: supported media, album limitations, and return values. The schema handles parameter semantics. Some context is still missing, such as whether only messages sent by the bot can be edited and what happens to the original text when media is added.

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. The description adds extra semantic context for the media parameter by defining what media types can be edited, how album membership constrains those types, and the special case of adding media to text messages—details not present 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 states a specific verb and resource: editing the media of existing messages, and explicitly lists supported media types plus the 'add media to text messages' case. This clearly differentiates it from sibling tools like editMessageText, editMessageCaption, and editMessageReplyMarkup.

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?

The description makes clear this tool is for editing media and adds album-specific constraints, but it does not explicitly contrast with sibling tools or state when to use editMessageText/editMessageCaption instead. Usage context is implied rather than explicitly delimited.

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