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

Annotations only establish the safety profile (not read-only, not idempotent, not destructive). The description adds real behavioral constraints beyond that: the target project must be deployed, rel_type must correspond to a schema key, and both node ids must reference existing nodes. It does not disclose duplicate-handling or failure behavior, which matters given idempotentHint=false.

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?

Front-loaded with the core action, followed by constraints and a clearly delimited example block. Every sentence earns its place with no 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 mutation tool with no output schema, the description covers prerequisites, schema-key matching, and example payloads, and annotations carry the safety profile. It stops short of describing duplicate/error behavior or the staging-vs-production default, so a small gap remains.

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 schema already documents all six parameters (baseline 3). The worked example supplies added value by showing concrete rel_type, from_id, to_id values and how the nested data object carries relationship properties.

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: 'Create a relationship between two nodes in a deployed graph project,' with scope ('deployed graph project') that narrows intent. It implies the singular counterpart to bulk_create_graph_relationships, though it never names a sibling 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?

Gives clear prerequisites: rel_type must match a project schema relationship key, and it directs the agent to get_graph_data_schema to discover valid types. It does not contrast with the bulk variant or create_graph_node, so routing guidance is incomplete.

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