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

The description adds useful deprecation context ('old v1') and a replacement instruction beyond what the annotations provide. It does not describe side effects, reversibility, or output, relying on readOnlyHint=true for the safety profile. No explicit contradiction with the annotations is stated, though the notion of 'joining' sits somewhat oddly with a read-only hint.

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 description is two terse sentences with no filler: 'The old v1 join. Use the join tool instead.' The key deprecation message is front-loaded and the alternative is stated immediately. It is concise to the point of being thin, but every phrase earns its place for a legacy alias.

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 deprecated tool whose intended use is 'don't call it, call join instead,' the description covers the critical routing context. However, it does not explain the three parameters, the return behavior, or why this variant is deprecated, leaving it incomplete if an agent actually needs to invoke this legacy endpoint.

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?

All three parameters (id, team_name, monthly_commit_usd) have no descriptions in the schema (0% coverage), and the description does not mention or explain any of them. Since schema coverage is low, the description was expected to compensate and failed to do so.

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 clearly identifies the tool as 'The old v1 join' and points to the replacement, with the title supplying the 'chain' resource. It distinguishes this legacy variant from the sibling join tool, but it never explicitly states the action of joining a chain in its own words.

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?

The description gives explicit routing guidance: 'Use the join tool instead.' This tells an agent not to invoke this legacy tool and names the exact alternative, which is the clearest possible when-not/alternative guidance for a deprecated tool.

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