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

Annotations only give the generic write profile (readOnlyHint=false, idempotentHint=false). The description adds real behavioral context: emails are sent to every signer, state moves Awaiting sign-off -> Decided (and locked), and it 'Needs permission to change tasks'. That auth requirement and the locking behavior are valuable beyond the annotations. It omits error/partial-approval 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?

The purpose is front-loaded in the first sentence and every sentence carries information about workflow or constraints. The em-dash asides ('You can ask; you can never sign -- a sign-off is a person, signed in') are somewhat stylistic and partly overlap with the schema's 'Not AI assistants' note. Overall efficient with minor redundancy.

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 mutating, email-sending tool with no output schema, the description covers the state machine, permission need, and who signs. The notable gap is the unexplained 'ref' parameter, which an agent needs to supply but cannot disambiguate. Otherwise it is adequately 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 coverage is 50%: the signers array is documented in the schema, but 'ref' has no description anywhere. The description reinforces 'the complete list of signers, by email' and that signers cannot be AI assistants, but it never explains what 'ref' refers to. It adds marginal value over the schema rather than compensating for the undocumented ref.

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 states a specific verb and resource: 'Ask board members to formally sign a decision off'. An agent can immediately distinguish this sign-off request from siblings like fenbs_add_decision or fenbs_update_decision. It stops short of naming any sibling explicitly, so it lands at a clear-but-undifferentiated 4.

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 workflow context ('Say what was decided first', 'it is Awaiting sign-off until all of them approve') so an agent understands this happens after a decision exists. However, it never states when NOT to use it versus update_decision or comment, nor any explicit alternative. Usage is implied rather than delineated.

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