things_complete_todo

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

With no annotations, the description carries the full behavioral burden, and it does disclose one real trait beyond the name: the item "goes to the logbook," i.e. a state transition rather than a deletion. However, the sentence is truncated ("as whe..."), so the actual completion-date/logbook semantics, reversibility, and any auth requirements are left unstated.

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?

A single compact sentence with the essential action front-loaded and the Beta marker clearly flagged is a reasonable structure. But the text is visibly truncated mid-word, so it fails to deliver a complete thought despite its brevity.

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 zero-parameter, no-output-schema tool this is close to adequate: it says what it does, where the id comes from, and where the item ends up. The truncation and the absence of any note about the schema/description id mismatch leave an agent with an unresolved question about how to actually call it.

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?

The schema declares zero parameters with 100% coverage, which would normally be a baseline 4, but the description asserts the tool operates on an id from things_list_todos while the input schema has no properties at all. That internal inconsistency actively misleads an agent about what to pass, so the baseline is lowered.

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 specific verb and resource ("Marks a to-do of Things 3 completed") and names the sibling that supplies the identifier ("by its id from things_list_todos"), so an agent can distinguish it from things_update_todo or things_create_todo. Docked one point because the sentence is cut off mid-clause and the referenced id is not reflected anywhere in the 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?

Provides a usable upstream chaining hint by naming things_list_todos as the source of the id, which is the main prerequisite for invoking it. There is no explicit when-not guidance, no mention of what happens if the id is invalid or already completed, and no differentiation from the other complete_* siblings.

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