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

Annotations already declare readOnlyHint=false, idempotentHint=true, destructiveHint=true, openWorldHint=false, so safety is covered. The description adds real behavioral context beyond that: the mutation is scoped to the agenda name only (blocks untouched) and it returns the full updated agenda. It does not explain why destructiveHint is true (the prior title is overwritten) or the auth/validation requirement on edit_token.

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?

Two tight sentences, front-loaded with the action and immediately followed by scope and return behavior; no filler. The return-value sentence is slightly redundant given an output schema exists, keeping it just below maximum.

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?

Low-complexity, two-parameter tool with a full schema, an output schema, and annotations, and the description covers purpose, mutation scope, and return shape. The only real gap is that token validity/rotation (rotate_edit_token is a sibling) is left entirely to the schema.

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% (both title and edit_token are documented, including that edit_token comes from create_agenda), so the baseline is 3. The description implies the title parameter is what changes but adds no format, length, or token-validity detail beyond the schema.

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?

Specific verb+resource ('Renames the agenda') that unambiguously narrows the broad name update_agenda to a rename-only operation. It also explicitly carves out scope against the sibling block tools ('Blocks are untouched — the block tools change those'), so an agent can distinguish it from add_block/update_block/remove_block without opening any schema.

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?

Clearly signals the context of use (title changes only) and routes block-level changes to the block tools, which is a genuine negative-routing statement. It stops short of naming other alternatives such as create_agenda or stating prerequisites (e.g., needing a fresh edit_token), so it is good but not exhaustive.

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