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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and closed-world, so the safety profile is covered. The description adds genuinely useful behavior beyond that: it returns metadata plus a capped UTF-8 text preview, and binary files yield metadata only, which tells the agent what to expect from the call. It does not cover error behavior for non-owned or missing files.

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 tight sentences with the primary action and ownership constraint front-loaded, followed by the return-shape caveat. Every clause earns its place with no redundancy.

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 rich annotations and an output schema present, the description need not explain return values, yet it helpfully summarizes them anyway and states the ownership requirement. Only a note on failure modes (missing file, foreign ownership) is absent, which is minor for a simple read tool.

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% with a single parameter, so the schema already documents file_id, its origin (list_data_feeds), and the ownership constraint. The description only restates 'owned by this agent', adding no format, casing, or sourcing detail beyond the schema. 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 (read) and resource (a user-uploaded file owned by this agent), which clearly separates it from siblings like get_data_feed, get_market_data, and list_data_feeds. The description also previews the return shape, so an agent can distinguish it from list/read tools without opening the schema.

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?

Usage is implied rather than stated: the schema notes file_id is 'returned by list_data_feeds', which hints at a discovery-then-read flow, but the description itself offers no explicit when-to-use guidance or alternatives. No exclusion criteria (e.g., when to use list_data_feeds or get_data_feed instead) are given.

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