Inspect Media Metadata in Message

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 profile is covered. The description adds useful behavioral context about its role as a pre-download verification step, though it does not describe behavior when a message has no media or when the account is unresolvable.

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?

Three short sentences, zero waste, and front-loaded with the capability before the sequencing advice. Every sentence earns its place: what it returns, when to use it, and what to use instead.

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-value documentation is unnecessary, and annotations cover the safety profile. With 100% parameter coverage and an explicit sibling hand-off, an agent has everything needed to select and invoke this tool 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 description coverage is 100%, so chat_id, message_id, and the optional account parameter are fully documented in the schema itself. The description adds no format or constraint detail beyond what the schema provides, which is the baseline for high-coverage schemas.

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 (inspect) and resource (media metadata attached to a message), and enumerates the exact fields returned (size, dimensions, mime type, duration). It clearly distinguishes itself from the sibling that performs the actual download.

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?

Explicitly prescribes the usage sequence ('Use before downloading to verify file attributes') and names the alternative tool ('To download the actual file, use `download_media`'). The when-to-use condition and the hand-off target are both stated, leaving nothing to inference.

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