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

Annotations only declare readOnlyHint=true, but the description adds major behavioral context: it NEVER returns a credential at any status, it returns three named states rather than a boolean, each response carries a next_action field, and 'claimed' is explicitly NOT success. It also tells the agent to independently verify via list_inboxes before asserting success.

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 action and the blocking bound, then the three states, then the verification warning. It is long and repeats emphasis ('NOT success', 'follow it literally') that could be tightened, but nearly every sentence carries actionable guidance for a genuinely tricky tool, so the size is mostly justified.

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 describing returns and does so: three named states with precise meaning, the next_action field, and the absence of a credential in any response. It also covers the cross-session continuation path via claim_connection_status. Nothing an agent needs to call this correctly is missing.

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 both parameters (claim_token and ttl_seconds) are already fully documented in the schema. The description only restates the ttl_seconds cap and the token's origin, adding no new syntax or format detail. Baseline 3 is correct when the schema does the heavy lifting.

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 and resource: block (up to ttl_seconds, max 60) for a human to finish the EMAIL+CODE step on the claim_url page produced by claim_trial_inbox. It explicitly distinguishes itself from the sibling tools by naming claim_url from claim_trial_inbox and by referencing claim_connection_status as the later check.

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 explicit when-to-use (block while a human completes the EMAIL+CODE step), what to do on each outcome (keep waiting or call again on 'claim_pending'), and names the alternative for later checking: 'call claim_connection_status later if you need to check again after this chat session'. It also warns that client installation can take arbitrarily long, so this tool only blocks up to 60s.

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