set_facebook_credentials

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

No annotations are provided, so the description carries the full burden. It discloses several critical behaviors: where credentials are saved (file path), that saving is merged with existing fields (non-destructive overwrite), that validation happens immediately via a specific API call, and the security property that app_secret is never sent elsewhere. These go beyond a simple 'store credentials' statement and include state-change and validation behaviors.

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 description is well-structured with intro, purpose, and parameter breakdown. It is appropriately sized for the complexity of the tool. The header sentence is front-loaded and each parameter line earns its place by adding unique information. Minor redundancy exists (e.g., repeating 'optional' in prose and schema), but the structure is efficient for a setup tool with security nuances.

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?

The tool has 5 parameters and a moderately complex setup/validation flow. The description covers storage location, merge behavior, validation call, parameter roles, and security boundaries. An output schema exists for the response, so return-value explanation isn't required. For a setup tool with security and validation aspects, nothing critical is missing.

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 0%, so the description must fully document parameters. It does this thoroughly: each parameter has a purpose, optionality/requirement status, and even usage notes (e.g., long-lived tokens recommended, app_secret never sent except to graph.facebook.com). The API version default is also specified in text, compensating for the schema's lack of descriptions.

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 ('Store'), a specific resource ('Facebook Graph API credentials'), and the immediate validation behavior. It clearly distinguishes this tool from siblings like check_facebook_credentials, get_credentials_status, and others by establishing it as the setup/prerequisite step.

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?

The description explicitly states 'Use this once before using any other tool', which provides clear usage timing. However, it doesn't explicitly exclude or compare against sibling tools that might also handle credentials (e.g., get_credentials_status), though the context is clear enough for an agent to infer when to use this tool.

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