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

Beyond annotations, the description adds the long-poll behavior of wait_seconds (up to 25 seconds, returning on state change or handoff end) and the no-API-key/no-account auth profile, which is genuinely useful. It does not explain the apparent tension with idempotentHint=false, i.e. that repeated calls with a wait can return different states, so the behavioral picture is helpful but incomplete.

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 first sentence front-loads the returned fields well, but the second sentence is syntactically awkward ('wait_seconds, up to 25, waits for...') and the third ('No API key, no account and no sign up') reads as marketing copy rather than operational detail.

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 no output schema, the description compensates by enumerating the returned fields, and it covers auth and the wait parameter. Only the interaction between read-only semantics and the non-idempotent wait behavior is left unaddressed.

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 schema already documents token, handoff_id, and wait_seconds thoroughly. The description only reinforces that either token works and restates the wait_seconds semantics, so baseline 3 is appropriate.

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 uses a specific verb (read) plus the resource (a handoff) and enumerates what is returned: state, payload, states, allowed transitions, and history. An agent can distinguish it from siblings like advance_agent_handoff or read_agent_run by the read-only framing, though no sibling is named explicitly.

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?

It implies the polling use case through wait_seconds: use it to block until the state changes or the handoff ends. There is no explicit when-not guidance and no named alternative, so the agent must infer that advance_agent_handoff is the mutating counterpart on its own.

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