ein_format_checkValidate US Employer Identification Number FORMAT (NN-NNNNNNN). No public EIN checksum exists.
| Name | Required | Description | Default |
|---|---|---|---|
| ein | Yes | US EIN, 9 digits; dashes/spaces allowed. |
| Name | Required | Description | Default |
|---|---|---|---|
| tool | No | ||
| scope | No | ||
| valid | Yes | ||
| reason | Yes | ||
| country | No | ||
| normalized | No |
Changes observed during successful MCP inspections. Dates show when Glama detected each change.
Input schema / examplesPrevious value: -[
- {
- "ein": "12-3456789"
- }
-]New value: +[
+ {
+ "input": {
+ "ein": "12-3456789"
+ },
+ "output": {
+ "reason": "checksum valid",
+ "valid": true
+ }
+ }
+]Output schema / examplesAdded value: +[
+ {
+ "reason": "checksum valid",
+ "valid": true
+ }
+]Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already establish read-only and idempotent behavior. The description adds an important limitation: only format validation is performed, with no checksum verification. This provides meaningful behavioral context beyond the annotations without contradicting them.
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?
One focused sentence conveys the action, scope, and key limitation. Every word earns its place, and the essential 'FORMAT only' point is front-loaded.
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 one-parameter, read-only, idempotent tool with an output schema, the description sufficiently covers the behavior, scope, and limitation. No critical operational detail 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?
The schema has 100% coverage for the single 'ein' parameter, so the baseline is 3. The description's format pattern adds slight reinforcement but does not introduce semantics beyond what the schema already documents.
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 ('Validate'), a specific resource ('US Employer Identification Number'), and a precise scope ('FORMAT (NN-NNNNNNN)'). This clearly distinguishes it from the many sibling identifier-checking tools.
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 makes clear this tool validates format only, and the phrase 'No public EIN checksum exists' explicitly warns the agent not to expect checksum/validity validation. It does not name alternatives or give an explicit 'use when' condition, but the use case is unambiguous.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool targets a distinct identifier type or on-chain data source, and composite wrappers like batch_validate and vendor_onboarding_pack are clearly labeled as batch operations. Minor confusion is possible among on-chain snapshot tools like balance_check, erc20_balance, and tx_activity, but the descriptions mostly resolve the boundaries.
Validators largely follow a predictable *_check suffix, with occasional format/validate variants like ein_format_check and company_number_format. On-chain and rental tools break the pattern with descriptive nouns such as block_info, tx_activity, and rental_verdict, so the naming is not perfectly uniform but remains navigable.
23 tools is a heavy surface for one server, spanning three distinct clusters: identifier validation, Base-chain inspection, and rental due diligence. Each tool has a clear purpose, but the set feels broad and could be split into smaller purpose-focused servers.
The identifier validation surface is well covered across many international formats and includes useful batch/package workflows. Minor gaps exist, such as no registry existence lookup for UK company numbers and no generic transaction-status tool, but the core due-diligence workflows are not left with dead ends.