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

Annotations already establish the safe-read profile (readOnlyHint, destructiveHint=false), and the description goes well beyond them: it enumerates every return branch of update.status with meaning ('available'/'current'/'unknown'/'gone'), notes the DELETED and un-shared edge cases, explains the FBB parent staying reachable, and states that non-snapshot copies return update: null.

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?

Front-loaded with the core question, and the dense status enumeration is necessary information rather than padding. The nested parentheticals make it slightly heavy to parse, but every clause earns its place.

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?

There is no output schema, so the description carries the full burden of explaining return values, and it does so completely, including the null case and each status meaning. An agent has everything needed to call and interpret the result.

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% for the single flowId parameter, and the description never defines it. The name is self-evident (the flow to check), so the practical gap is small, but the description adds no semantic detail beyond what is already obvious from the parameter name.

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 question the tool answers ('Has the build this flow was copied from released a newer version?') plus the two sourcing cases it covers (a listing clone and an FBB build). It is clearly distinguishable from the sibling flow_get_upstream_update, which it names as the follow-up for reviewing an available update.

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 a concrete trigger ('safe to call whenever the user asks about updates') and routes the agent to flow_get_upstream_update when status is 'available'. It does not spell out when-not to call or the cost relative to other checks beyond 'cheap', but the guidance is clear and actionable.

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