Add Observations

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

Annotations already declare this is a non-read-only, non-destructive, non-idempotent write, so the safety profile is covered. The description adds the useful constraint that target entities must already exist, but says nothing about duplicate accumulation (relevant given idempotentHint=false) or error behavior for unknown entities.

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 efficient sentence with the resource and scope front-loaded. Nothing is wasted, but at ten words it is close to under-specified rather than optimally concise.

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?

An output schema exists, so return values need not be explained. However, for a mutation tool with an unannotated parameter structure and a non-idempotent flag, the description should at least cover append semantics and the failure mode when the named entity does not exist.

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?

Reported schema description coverage is 0%, and the description contains no parameter guidance at all — nothing about the observations array, its entityName/contents fields, or the fact that observations are appended rather than replaced. The nested schema properties carry some of this, but the description does not compensate for the coverage gap.

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 + resource: 'Add new observations to existing entities in the knowledge graph.' The qualifier 'existing' implicitly separates it from create_entities, though the sibling is never named explicitly.

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?

Usage is only implied: the tool is for appending observations to entities that already exist. There is no explicit when/when-not guidance or routing to siblings like create_entities (for new entities) or delete_observations (for removal).

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