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

With no annotations present, the description carries the full burden and does meaningful work: newest-first ordering, limit/offset pagination, the next_offset-null end-of-page sentinel, and the X-API-Key auth requirement on the MCP connection are all disclosed. What it omits is rate limiting, page-size bounds, and an explicit read-only statement, so it falls short of fully covering behavior.

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, front-loaded with what the tool returns, followed by pagination mechanics and the auth prerequisite. No filler, and the most decision-relevant information leads.

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?

For a simple two-parameter, zero-required list tool with an output schema, the description covers fields, ordering, pagination, and auth — enough to invoke it correctly. Only the missing sibling routing and explicit read-only framing keep it from being fully complete.

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% and neither parameter has a description, so the description must compensate. It names limit and offset and ties them to pagination, and mentions the next_offset sentinel on the response side, but gives no valid ranges or units beyond the schema defaults.

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 clear resource (leak canaries) and enumerates the returned fields (counterparty, mode, reaction on leak, event count), so an agent knows exactly what comes back. It does not explicitly distinguish itself from the nearby siblings canary_events and canary_issue, so differentiation is left to the reader.

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?

There is no explicit when-to-use or when-not guidance and no named alternative, even though canary_events and canary_issue sit right next to it. 'Your leak canaries' weakly implies listing one's own canaries, but routing between the three canary tools is left entirely to inference.

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