session

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

Annotations provide idempotentHint and destructiveHint, but the description adds a concrete side effect: 'On complete, persists a session note to the vault.' This goes beyond the annotations and helps the agent anticipate a persistent effect. It does not contradict any annotations and provides useful behavioral context.

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 sentences, front-loaded with the primary purpose, and every word contributes. It is concise without being under-specified, effectively summarizing the tool's core behavior and a key side effect.

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?

The tool has 13 parameters but only 1 required, and the schema provides detailed descriptions for all. The description adds the important side effect of persisting a note to the vault, which is not in the schema. Given the high schema coverage and clear summary of actions, the description is sufficiently complete for an agent to understand the tool's role and main behavior.

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 description does not need to compensate for undocumented parameters. The description mentions 'register, update, or query' which aligns with the 'action' enum, but it does not add meaning beyond what the schema already provides for individual parameters. Baseline of 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 clearly states the tool's function: 'Register, update, or query active agent sessions for multi-agent coordination.' This includes a specific verb ('register, update, query') and resource ('active agent sessions'), making it unambiguous and distinct from sibling tools, none of which handle sessions.

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 context ('for multi-agent coordination') indicating when it might be used, but does not explicitly state when to use it versus alternative tools, nor when not to use it. There is no mention of exclusions or preferred alternatives, leaving the agent to infer usage from the purpose.

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